I Am Going To Read Your Mind.

Okay, so I have a psychology test on Monday and since I've already revised a fair bit of Cognitive, I'm going to post on Developmental.
At the moment we're studying attachment and I don't like my teacher because she's annoying imo.

So anyway, what is attachment? Well, there's a definition I need to learn - attachment is a strong emotional and reciprocal bond between two people (especially an infant and caregiver(s)). It serves to maintain proximity as both experience distress when separated. Attachment also serves as a basis for later emotional development.

Now, all the mumbo jumbo is out of the way, lets get on with some real learning.

Maccoby is a guy who said that we can tell when two people have an attachment because of how they behave. These behaviours include - seeking proximity, separation anxiety, joy at reunion and general orientation.

Now, why do we form attachments? Many people would argue that it's purely on an evolutionary basis - that babies need to bond with the mother in order to maintain the care, food and safety she provides. Newborn humans are born helpless and remain so for a long time after birth, so we need to keep a close relationship with our parents in order to survive and continue the species. However, there are also some short term benefits to attachment, such as the fact the caregiver we bond with supplies us with food, protection and education, and other general skills that we'll need as we grow older.

It's also evolutionary beneficial for a parent to remain close to the infant as they've put a lot of resources and energy into rearing the infant and need to ensure it lives through to adulthood and reproduces. Finally, its been argued that attachments provide us with a schema which will help us form attachments later in life. Some have also argued that attachment discourages incest, which would be very bad for the species.


So then, how and when are attachments formed? It's believed that they're formed very early on, and this is especially try for birds who imprint on their parents within the first 13-16 hours after hatching. This was proven by Lorenz's geese experiment. Lorenz also learnt from his experiment that if imprinting didn't occur within the 32 hour critical period, it wouldn't happen at all.

All of these processes are also true for humans - we too form bond in the early stages of life, and if we fail to bond within the first year of our life, it becomes very hard to, and after five years it's impossible. When and how we bond with our parents makes a big difference on the relationship we have later on with them. This is shown in Klaus and Kenell's 1976 experiment on newborns in America.

It has been found that at around 7 or 8 months babies begin to show real signs of attachment. According to Shaffer and Emerson's 1964 study, babies under the age of 3 months will accept care from any human. After 4 months however, the baby will start to show preference to certain people and by 7 months one or maybe two specific and special attachments would have been formed. After 9 months, the baby is ready to develop multiple attachments, such as with siblings and grandparents. The study carried out by Shaffer and Emerson has a high ecological validity and is ethically sound.



There are several explanations for attachments, and we can split them into two groups. First we'll take a look at Learning and Behaviour Theories of Attachment. These theories say that all behaviour is learned and not innate, as many people believe.

Classical conditioning, is what it says on the tin - classical. The idea is that the baby associates food (a necessity of life) with its mother in the early stages of life and carries this love of the mother through to the rest of their lives. In this case, before conditioning, the baby has an unconditioned stimulus (food) and an unconditioned response (happiness). During conditioning the mother becomes the neutral stimulus who just comes along with the food. As time passes, the child will be conditioned to respond happily to the mother alone.

Another learning and behaviour theory is Operant Conditioning and Attachment. This is the idea of learning by enforcement. There are two types - negative and positive. Two examples below -

Behaviour = crying --> food = positive reinforcement to cry

Behaviour = crying --> food = negative reinforcement for the mother to feed the child.

However, food isn't always necessary to form an attachment, as Schaffer and Emerson found that 39% of babies formed an attachment to people who didn't feed them, such as grandparents. This gives us the theory of comfort over food, which is backed up by Harlows 1959 experiment on monkeys. I can't be bothered to go over the ins and outs of this experiment because I know it all anyways :)

Finally in the learning and behaviour theory is Social Learning Theory, which is just for a couple of extra marks in the exam NOT a key point. Bascially, social learning theory is the idea that -

• children copy affectionate behaviour between their parents
• parents watch their children and encourage appropriate behaviours
• parents teach their children to be affectionate. 

Now, we can move onto the second category - Evolutionary Theories of Attachment. 

One of the biggest theory is Darwin's Evolutionary Theory, which shows us that attachment is necessary because it keeps the infant close to the parents and hence keeps it safe. It allows the infant to explore within a secure base and to develop a loving and reciprocal relationship which is passed on through generations. 

Now we come to Bowlby who's a big guy when we talk about all this. He was mainly interested in the caregiver-infant relationship and produced a theory of attachment by combining Freud's ideas with the ethological concept of imprinting. There are seven key principles in Bowlby's theory, so I'll list them below.

• Adaptive and innate - Bowlby believed that although children form several attachments, only one is of significance and the rest form a hierarchy. He believed that the primary attachment belonged to the person who responded best to the infants social releasers. This bond also forms the foundation for future relationships and the infants development. 
• Social releasers - children have an innate drive to becomes attached as it has long term benefits, so that have characteristics which encourage caregiving. 
• Monotrophy - this is the idea that an infant has an innate readiness to have an attachment with its mother.
• Sensitive period - Bowlby believes that there is a crucial period of 2.5 years to form an innate attachment.
• Secure base - the idea that the infant forms attachments in order to have a secure base from which to explore and grow.
• Internal working model - theorizes that children learn what to expect from a relationship from how their attachment to their primary caregiver is. 
• Continuity hypothesis - is the idea that there is a link between early attachments and later emotional behaviour. 

Now I'm stopping here and coming back to all this at a later point.

Joy, I'm back to finish off this nonsense.

Okay, so I'm just gonna write a brief summary and evaluation of Bowlby's theory -

Summary -
Bowlby theorized that all children formed a hierarchy of attachments, the primary being the most important  as it supplies a safe environment to learn and explore, ensures they have food and protection, and forms a basis for future relationships. Bowlby believes attachments are innate and are forms before two and a half years of age.

Evaluation -
Mothers may not be as important as Bowlby believes as infants form a wide range of attachments with people other than their mother. Bowlby didn't discount multiple attachments even though Shaffer and Emerson found that multiple attachments are the rule rather than exception.  Bowlby also believes that the father has no or very little emotional importance (this could be due to when and why the research was carried out), yet Shaffer and Emerson have proven that fathers are attachment figures in their own right.

Basically, Bowlby may have overestimated the importance of the mother, although he did accept that a 'mother-figure' could stand in and provide satisfactory attachment. In addition, Lamb's studies have shown that male infants show preference to their father over their mother.

And finally, we need to consider that Bowlby's theory may just be too simplistic to explain something as complex as attachment. Today, infants no longer need protection from predators but attachment still plays a crucial role - Bowlby fails to explain why this is and hence makes his theory reductionist (it ignores culture and technologies of the present day).



And I think that just might be Psychology done and dusted. We shall see how the test goes, I suppose.

A Rant About Cells.

No one warned me that A Level Biology was going to be this hard. I’m shocked and amazed that I managed to drag myself through my homework this morning. So here I am to revise. I’d like to think I’m on my blog, but my internets down so this is just in Word until it’s fixed and I can put it up. So there.

I’m gonna go over Cell Structure today because it’s what I’m struggling with the most; I’ll probably do Neucleic Acids another time.

Okay, so cells are the basic unit of life, and there are two types. Type one is Eukaryotic, which are cells that have a nucleus, such as plant and animal cells. Type two is Prokaryotic, which are cells with no nucleus, such as bacterium. There are two types of microscopes we can use to look at cells – light microscopes and electron microscopes. We can see in a much finer detail with an electron mircoscope because the wavelength of electrons is shorter than the wavelength of light. Electron microscopes revel the fine structure or the ultrastructure of a cell, which is what I’m going to be going into more detail about in a moment.

Okay, so a Eukaryotic cell is surrounded by a plasma membrane, and is filled with cytoplasm. I’m trying to think of a good anology for this, but all I can come up with at the moment is a blister or a water balloon. Oh, and there are structures inside the cell which are called organelles.

These organelles can be divided into two groups –

Structures composed of or surrounded by a membrane:

•          Nucleus
•          Chloroplast
•          Mitochondrion
•          Endoplasmic reticulum
•          Golgi apparatus
•         Lysosomes

And structures not composed or surrounded by a membrane:

•        Ribosomes
•          Centrioles

And now I need to go into detail about all the cell boundaries before I can go into detail about organelles.

So then. The most obvious cell boundary is probably the cell membrane, but for A Level it’s been renamed plasma membrane. Now, the term ‘unit membrane’ is a term used to describe all the following:

•          Plasma membrane
•          Membranes of the nucleus, mitochondrion, chloroplast, endoplasmic reticulum…etc
•          And to describe the structure (see section 1.3)

What’s important to remember is that membranes within the cell cordon off areas where this is no cytoplasm so other things can be stored such as harmful chemicals or enzymes. They’re kept within membranes so they can’t damage the rest of the cell, sort of like when they put someone in isolation at school, its so they can’t infect the rest of the student body.

Also, membranes within the cell provide a huuuuuuge surface area for various things such as the attachment of enzymes (eg. in the synthesis of ATP in mitochondrion membranes), and guess what, that’s not all they do. They also provide a transport system within the cell (eg. endoplasmic reticulum).

One final note on the plasma membrane – microvilli are infoldings of the membrane and are used to increase surface area (eg. in the digestive system).

Now then, the cell wall. It’s fully permeable, so pretty much anything can get through it. It’s like putting a wimp in charge of entrance to a nightclub, anyone’s gonna get in. But, really, that wimp is made of tough fibres embedded in the matrix of polysaccharides (and other sugars). But, despite letting anyone and anything in, the cell wall does keep the cell nice a strong and rigid. On the downside, there are a couple of gaps in the wall, AKA pores, which allow cytoplasmic channels called plasmodesmata to flow between cells.

Now those are all done with, I can get on with all the different organelles. These are the little bits and pieces you get floating around in the cytoplasm. Like the little bits you get in non-smooth orange juice.

So, most importantly is the nucleus. It’s so important because it regulates all the functions within the cell. Essentially it’s the brain of the cell, but I’m not allowed to say that in the exam. Like the huamn brain is housed inside the skull, the nucleus is housed in a a nuclear membrane or envelope. This membrane, like many others I’m going to mention, is a double membrane.

The outer membrane is joined up with the endoplasmic reticulum and possess ribosomes, wheras the inner membrane has nothing to do with the outside world. Both the membranes fuse every so often to make pores so things can get in and out.

Inside the nucleus is an interesting place – it’s filled with a material called nucleoplasm (gotta give it to those Biologists, they’re original with they’re naming of things). Anyway, there are some structures within this nucleoplasm. Joy, there are just structures within structures within structures. I can’t cope. But must plough on.

Right, so what does the nucleolus do? For one thing it makes RNA and assembles ribosomes. The nucleolus is also the home of all the little chromosomes, which contain hereditry DNA and are pretty much the instruction manuals for the cell.

And that’s pretty much it for the nucleus. Ready to move on? No? Too confusing? I’m gonna say tough, just like my teacher did….

So then, the mitochondrion provides the energy for the cell to do all its bits and pieces. They’re rod shaped and vary in size (0.5µm wide and 7µm long). You can find the mitochondrion doing the most work in active cells such as in the liver, muscles and kidney, because these cells require the most ATP (energy).

Again, this is a double membrane organelle. The outer membrane is smooooooooth, whereas the inner is folded to form cristae. This is needed for a large surface area for enzyme attachment. Cristae are also the home of Oxidative phosphorylation (a stage in aerobic respiration). Oh, and the cristae also have stalked particles where the enzymes for ATM synthesis are kept.

The inner membrane has just as much action as the outer – it contains ribosomes, a loop of DNA and enzymes.

And that’s a neat little way of finishing off the mitochondria.

Next up are chloroplasts, which everyone knows are involved in photosynthesis in plants. They convert light energy into chemical energy which is stored in food molecules for the plant to gobble up. Chloroplasts are disc shaped and are like tinnnnnny, I’m talking 1-4µm in diametre and 1µm thick. Oh, and they’re green because of the presence of chlorophyl, so there’s no need to stain the cell if you want to see them with a light microscope.

This is another organelle with a double membrane, but unlike the mitochondrion, both membranes are smooooooth and have no folds. Inside the inner membrane is the stroma, where DNA, ribosomes and starch grains are stored. Like the nucleus, this is an organelle with bits and bobs all inside of each other. Inside the choroplast there are internal membranes called thylakoids (when you stack them together you have to call them a granum). These thylakoid thingies increase surface area for the attachment of chlorophyll pigments.

Oh, and chloroplasts also have enzymes for the light-independent reaction of photosynthesis.

As you might have noticed, chloroplasts and mitochondria were quite similar, but what’s next are rather different.

Ribosomes are these tiny little dots that seem o just float about a bit. They’re actually very small particles of RNA and are made in the nucleolus. They’re made of two sub units, the light unit and the heavy unit (if I look back in my notes I can see the measurements because I can’t be bothered to figure out how to type that little symbol for microns again. Anyway, ribosomes are found floating free in the cytoplasm and boung to membranes such as the rough endoplasmic reticulum. These guys are kinda like that person you can always see wandering your local shopping centre. They’re always there, just bopping around with not much to do. BUT! Ribosomes do have something to do. They make protein. Dun dun dunnnnnnnn.

And that’s all I have to say on ribosomes.

Endoplasmic reticulum however, is going to take a long time. Basically, the ER is a network or membranes running through the cytoplasm of every cell. The places between the membranes are called cisternae. There are two types of ER, rough ER and smooth ER, so to save myself the bother of witty prose, I’m gonna bullet point on each type.

Rough ER:

·         Ribosomes (which make it rough)

·         Involved in making and transporting proteins

·         Very prominent in enzyme secreting cells, such as the pancreas

Smooth ER:

·         No ribosomes

·         Involved in making and transporting lipids (fats) and steroids

·         Detoxifies poison

·         Extensive in steroid hormone-secreting cells, such as the testes

Magically, that’s the endoplasmic reticulum all done and dusted.

Now, lets tackle the golgi body/apparatus/complex. This is an organelle made of membranes, they’re all curved and stacked one on top of the other. The spaces between these membranes are called the cisternae. And basically, what the golgi body does is act like a post office, in that it receives, sorts and delivers loads of different molecules.

The two main functions of the golgi body are; sectretion, when it produces secretory vesicles, and ; intracellular digestion, when it produces lysosomes.  How does it do these things? At this point I should be flicking forward a few pages in my file to find Figure 5, 6 and 7 because they talk me through the whole thing in laymans terms. Well, ish.

Now, in the whole golgi body process thingy, something called vesicles are mentioned. These are small membrane bound structures and they come in two types – secretory vesicles and lysosomes (funny, where have I heard those terms before? *Note: in a sarcastic tone*)

Lets talk about these two different types of vesicles. The secretory vesicles contain (for example) mucin and are produced by cells lining the gut, reproductive and respiritory systems, or (for example) digestive enzymes which are produced by pancreatic cells. The contents of the secretory vesicles is determained by the type of cell.

Lysosomes on the other hand, are not usually released from the cell and contain digestive enzymes.

Woo, only two more organelles which I haven’t covered yet, but I’ll get back to those as soon as we’ve done then in class J

I’m back, finally, because we’ve finished Eukaryotic cells in class, so I’m just gonna go over vacuoles and centrioles.

Vacuoles are different in plants and animals so I’ll just list them.

Plants;

·         Biggggg permenant vacuole

·         Single membrane called a tonoplast

·         Contains a fluid called cell sap which contains chemicals like glucose

·         It provides support of young tissues

Animals;

·         Large numbers of small tempory vacuoles/vesicles

·         Functions: taking up food and removing waste

NB – Vacuoles are larger than vesicles, but otherwise there’s no structural difference.

Now, finally centrioles. They’re only found in animal cells and are basically hollow cylinders and come in pairs. The separate from each other during the early stages of mitosis and are associated with the separation of chromosomes during cell division.

And that’s all I need to know on Eukaryotic cells. I’m dreading Prokaryotic, if I’m honest. Now this is being posted to the blog.

Wowwww, this is long.

There's A Law For Everything Nowadays.

Okay, so this is gonna be super quick but super long ICT run through in prep for my exam tomro.

Okay, so in the CPU, there are 3 main parts -

The control unit, which controls all the operations going on.

The ALU (Arithmetic and Logic Unit), which does all the calculations and logical opperations.

And finally, the Immediate Access Store (main memory), which holds current programs or the ones waiting to happen.

There are a couple of typed of computer and I know all the details of them all, but here's the list anyway -

Mainframe

Microcomputer

Laptop

Palmtop

Embedded computer

Again, another thing I know all about are bits and bytes. One bit is either a 0 or a 1, and one character is equal to a byte, or 8 bits. There are 1024 bytes in a kilobyte, 1024 kilobytes in a megabyte, and 1024 megabytes in a gigabyte.

There are two types of memory in a computer - RAM and ROM, which again, I know all about.

But, there's a bunch of different types of backing storage, listed below...

Magnetic Tape -- used for backup and archiving

Magnetic Hard Tape -- fast storage + access to data, not portable, more data than a floppy and robust.

Floppy Disk -- portable, easily damaged

ZIP -- portable, special ZIP drive needed, up to 250Mb on disc

Disk Cache -- temporary, fast

Optical Disks -- laser technology used to read data

CD-ROM/DVD/CDRW -- stores more data, portable, expensive.

Then there's a huge amount of input and output devices, and different types of software which I know all about, so I'm moving straight on to types of operating system.

There are loads in my booklet, but I'm just gonna go over the main 3 for GCSE level. They are -

Batch Processing System -- which collects and groups data, then processes it at a later stage. This is used for payroll, stock control and billing systems.

Realtime Systems -- when inputs immediate affect the outputs and timing is critical. This is used for the control of nuclear power plants, oil refining, chemical processing and air traffic control.

Realtime Transaction -- when inputs immediately affect outputs but timing isn't critical. This is used for not so dangerous things, like airline booking systems.

Now, on to HCI (human-computer interfaces). Most modern computers operate though GUI's, and have added features like on screen help, customized user environments, on screen assistants and tutorials.

Advantages -

- user friendly

-minimum training

- run more than one piece of software at once (so easy to transfer data)

Disadvantages -

- take up more RAM

- makes the PC run slower

Okay, and now I've lost my patience with this. Ah well.

...It Builds Character

Hellooo.

Crash course on freewill and evil and all that jazz coming up...

Okay, so the freewill defence is the Christian excuse for pretty much everything. While an atheist might question why God lets evil things happen to us, Christians just dismiss the whole thing by saying that God has to let these things happen because he granted us freewill.

The basic idea is that, if God stopped a man stabbing another man, it would remove the mans freewill to commit moral evil. If evil didn't exist, people wouldn't have the choice between good and evil and hence no freewill.

And this magnificent argument covers Christians backs for natural evil too - if there was no threat of natural evil and everything was predictable, people wouldn't be able to learn from the consequences of natural evil. Freedom not only means choice, but also the consequences of choice. Things being to predictable would remove the value from life. The unexpected gives us the chance of total disaster and total triumph.

Now then, Karma. It's usually a philosophy found in Eastern religions like Buddhism, Sikhism and Hinduism. Karma's basically the law of consequences - if you do something bad, then you have to deal with the consequences, and if you do something good, then you get to reap the benefits. These consequences might come tomorrow, next week or in your next reincarnation. If you're especially good, you might get a reward or get to develop certain qualities of your soul.

The idea of Karma and evil is different for the 3 main Eastern religions, so here they are below;

• Hinduism - the challenge is for everyone to achieve moksha and escape the cycle of reincarnation. This is done by not building up any karma, and your soul isn't reborn anymore, so suffering and evil don't matter to you.
• Sikhism - this is super simple... doing good deeds leads to good rewards and doing bad things leads to bad consequences.
• Buddhism - the whole point of being a faithful Buddhist is trying to live a life free of desire, hate and delusion and reach true enlightenment so karma can be left behind.

Now, as I mentioned in my previous post, sometimes we need evil in our lives to help us learn and become better people. We can also become better people through evil by helping others. There's loads of examples of this, like Mother Theresa, the Buddhist monks trying to get rid of oppressive rules in Tibet, Gandhi getting rid of social inequalities in India, fighting discrimination like Mandela did in SA and loads more, like the Salvation Army, Muslim Aid and caring for the needy in the locality of the gurdwara like Sikhs.

Basically, evil brings out the best in people because it gives us all opportunities to over come it and help others in need.

I'm really bored of typing right now, so I'm just going to bullet point all the arguments for the need of evil and suffering -

• People would be selfish if there wasn't people suffering and in need
• Suffering brings home to well-off people how lucky they are and inspires them to help
• Buddhists see suffering as part of life that has to be dealt with
• Jesus experienced all the pain and suffering that humans experience, so God understands suffering
• Muslims have zakat (when they give a percentage of their annual salary).

Wow, thank goodness for that.

Fingers crossed for a good result in RS like last year!

You've Been A Very Bad Boy.

Is God willing to prevent evil, but not able?
Then he is not omnipotent.
Is he able, but not willing?
Then he is malevolent.
Is he both able and willing?
Then whence cometh evil?
Is he neither able nor willing?
Then why call him God?

That quote was written by Epicurus, who lived from 341 to 270 bc and this guy seems to have hit the nail on the head when it comes to the problem of evil.

There always has been and always will be evil things or people on earth, and in my opinion, that's the one thing that can fully disprove the existence of God, thanks to that philosophy of Epicurus'.

The above philosophy helps us question the existence of God in relation to the extent of his power and the extent of his love. For example, if God is all-powerful, why doesn't he stop bad things happening to humans, his ultimate creation? Has he just decided not to protect us and use his power, or is he not powerful enough? Not being powerful enough is basically saying that evil is more powerful than God, so God cannot be called all-powerful and hence is not God.

We can apply the same thing to God being all-knowing and all-loving. Does he not know that evil things happen? Does he not love us enough to care about evil things happening? If the answer is no, then why doesn't he stop evil things happening?

Which brings us about to the ultimate question - should God interfere in human life? It's the same principle as a mother interfering in her child. Should she protect her child from everything and cause the child to suffer as soon as she's not around? Or should she allow the child to suffer in moderation so the child can learn and grow?

But then, maybe God should only prevent certain types of evil. We can divide evil into two camps. Natural evil and Moral evil.

Natural evil is exactly that; natural. It's caused by the structure of the Earth and the universe - think of tectonic plates causing earthquakes and volcanoes. These things cause hardship and suffering for humans, so should God get rid of them? But if God removed all of these hazards, earth and the universe wouldn't be able to support life, and therefore we wouldn't exist so God wouldn't have anything to protect.

Moral evil is more complex. It comes from humans and their sin, apparently. Moral evil can range from jealousy to murder. Can God protect us from all these things? The simple answer is no - things used to commit moral evil can also be used for good, such as a surgeons scalpel. But another question can be asked - what is the root cause of moral evil? Guns don't fire themselves and bombs don't appear from thin air, all of these things come from humans. So why do we create and use them in the ways we do?

Which brings us nicely along to the origins of all evil. We can look at the story of Adam and Eve. They were told not to eat from the tree, and the serpent encouraged them and they did. God gave Adam and Eve freewill to choose whether or not to eat from the forbidden tree, and they did so despite his warnings. Because of this, God punished Adam and Eve - he made humans and serpents enemies, gave women the pain of childbirth, made men dominant over women, and he made it hard to harvest the land. Then God cast Adam and Eve out of the Garden of Eden, but he couldn't take away their knowledge of good and evil, which they'd gained from the forbidden tree.

Another origin of evil might be the story of Ibilis. In short Ibilis was an angel who refused to bow down to God's greatest creation - mankind. So God banished Ibilis from paradise, so Ibilis vowed to persude humanity not to follow God. So God said that he'd fill hell with Ibilis and all his followers. It's then apparently Ibilis who leads Adam and Eve astray.

Overall, religious stories of the origin of evil very rarely put the blame on God, and evil is considered to have come from the misuse of freewill and goes against God's will. The main idea is that God allows evil to go ahead, but doesn't will it.

The next question I'm going to look at is whether or not we need evil and suffering.

A central answer to this question would be that was need evil and suffering as a contrast to help us appreciate good things. If all things were good, we wouldn't be able to appreciate them, so by having evil too, we can appreciate the good and bad things in life in relation to each other.

Another argument would be that God only created good, and evil came from the misuse of freewill and denial of God. God couldn't have created evil as it's apparently not in his nature, so evil must have come from elsewhere and spoilt God's image.

We can also look at evil and suffering as important learning experiences in this life, as this life can be regarded as a preparation for our next life. This is called soul-making, and evil can be looked upon as a learning tool for this life. It can also be a learning tool for this life, as we can learn from mistakes made by ourselves and others to improve this life.

And that's all I'm going to write on tonight, and my next post will hopefully be on the Free Will Defence, Karma, believer's responses to evil, and whether or not people need evil and suffering.

Boom, job done.

Pre-Exam Panic.

A quick run through of tests for just about everything I need to know.

Simple place to start is flame tests.

You grab a powdered substance and burn it and see what colour it turns - here's the list...

Sodium - Yellow/Orange

Potassium - Purple

Calcium - Red

Magnesium - Really really bright.

Now, how to test for metals in compounds dissolved in water....

Zinc - you need to add sodium hydroxide drops IN EXCESS - White precipitate (which goes away in excess sodium hydroxide solution).

Copper(II) - add sodium hydroxide drops - Light blue precipitate

Iron(II) - add sodium hydroxide drops - Green precipitate (that eventually turns reddish brown)

Iron(III) - add sodium hydroxide drops - Reddish brown precipitate

Magnesium - add sodium hydroxide drops IN EXCESS - White precipitate (that's here to stay, regardless of excess sodium hydroxide solution).

Here's the equation for those lot ---

eg. Copper Sulphate + Sodium Hydroxide ---> Sodium Sulphate + Copper Hydroxide

CuSO4 + 2NaOH ---> Na2SO4 + Cu(OH)2

Now then, here comes the hard bit. First of all, these are tests for halide ions in water. We're technically testing for anions (the negative bit that conducts electricity or something... basically, the Surname of the chemical).

Chloride - add dilute nitric acid and silver nitrate solution - White precipitate

Bromide - add dilute nitric acid and silver nitrate solution - Creamy white precipitate

Iodide - add dilute nitric acid and silver nitrate - Yellow precipitate

Sulphate - add dilute hydrochloric acid and barium chloride solution - White precipitate

Nitrate - add sodium hydroxide to solution and warm it up, then add aluminium powder and test the gas produced - Red litmus turns blue (Ammonium produced)

Now, to identify anions in solids, we need to add either dilute hydrochloric acid or sulphuric acid to the solid, then pass any gas produced through limewater. If the water goes milky/cloudy, the solid is a carbonate.

There are two solid carbonates, and we can identify them because Copper(II) carbonate is a green solid which when heated goes black and gives of CO2.

Meanwhile, Zinc Carbonate is a white solid and goes yellow when heated and gives of CO2.

And finally, the easy tests on how to identify gases.

We all know that oxygen relights a burning splint, hydrogen produces a squeaky pop and carbon dioxide turns limewater milky. But I also need to know that chlorine chlorine turns damp blue litmus paper red then white. And I need to know that ammonia turns damp red litmus paper blue :)

Lurrrrrvley, I'm done for this evening.

Ciao Ciao!

In The Limelight.

Today's post will be on limestone because I have my Chemistry exam on Wednesday and I've hardly looked at this topic. It's a small one, but I think it'll be worth quite a few marks, knowing my luck.

So, the syllabus says I need to know about the thermal decomposition "of the carbonates of calcium, copper and sodium", but today I'm just going to focus on calcium carbonate because it has the most to do with limestone.

Thermal decomposition is when something gets so hot that it's forced to break down into the chemicals it's composed of, so in the case of Calcium Carbonate, you'd get Calcium Oxide and Carbon Dioxide. To get that to happen though, you have to raise the temperature to about 1200 degrees Celsius, which is mighty high.

But, we do it anyway because broken down Calcium Carbonate is pretty useful. You see, this Calcium Oxide is also called quicklime. We make it put crushing some limestone, then chucking it in this rotating drum with some air. Then we burn some fuel to get lots of heat (1200 degrees) and out comes CO2 and quicklime (Ca0). And this quicklime can be used for all sorts of things - we can put it in soil to neutralise acidity, we can use it to make steel from iron and some industries use it as a drying agent.

Then, if you add some water to the quicklime, you get an exothermic (gives out heat) reaction that gives you slaked lime. Which is also pretty useful - it can be used to neutralise soil acidity, to make mortar for buildings, to make pottery, and in a solution makes limewater to test for CO2.

But, limestone on its own is also really useful -here's some stuff it can do;

-can be crushed and used for road building,

-can be added as a powder to lakes to neutralise acidity,

-can be mixed with clay to make cement,

-can be used to extract iron in the blast furnace,

-can be heated with soda and sand to make glass and,

-can be used to neutralise acid gases give off by power stations.

Which is all great, and the trade for limestone is great - the UK quarries over 65 million tonnes per year, and there's loads more in the rest of the world. But, Quarrying is a bit of an environmental issue because they're great big holes in the ground which look pretty ugly and dirty.

Now, for some equations.

Here's the one for the thermal decomposition of calcium carbonate (limestone) -

CaCO3 ------> Ca0 + CO2

And this is the one for turning quicklime into slaked lime -

CaO + H2O ------> Ca(OH)2

Tahdah, thats limestone covered :)