explosion compilation

Thanks to Conor for sending the videos in, and my Btec group for managing to get through the year without me killing one of you.

And well done to Jack for catching that bottle, very impressive.

thermit update

Different class, same experiment.

This one shows nicely why you lot were on the other side of the room.

Thanks to Arran for the video.

Still not Thermit

thermit reaction

Been doing displacement reactions involving metals with Year 9 classes this week, and there is no finer example than the reaction of aluminium with iron oxide. Also known as the Thermit reaction, the vast amount of energy released is enough to create molten iron, which in days of yore is enough to explain its use in welding railway lines together. The trouble is, it has a high activation energy and requires a magnesium fuse to get the mixture going, as seen in the video below.

aluminium + iron oxide → aluminium oxide + iron

2 Al  +  Fe₂O₃  →  Al₂O₃  +  2 Fe 

The aluminium is far more reactive than the iron and so displaces it in a violent reaction.

I like the second video here as it shows the large volume of smoke rolling over the ceiling as the reaction goes off.

 

Thanks to Jodie and Daisy for sending the videos in. 

Not the Thermit

use the force

I'm a bit obsessed with the periodic table at the minute. More so than usual, just to clarify.
So I've been looking for some different versions.

How about this then, based on the land of Middle Earth, which is surprisingly well presented and organised.

Or this one based on The Empire Strikes Back (use link for larger version), widely recognised as the best of the Stars Wars films.

Who's scruffy looking now?

If anyone finds any other good examples, let me know. And if you find them on a website without the word 'geek' in the web address I'll be even more impressed.

My personal favourite could well be this one though. To the untrained eye it looks like a regular periodic table, but chemistry reckoned without Chuck Norris.

You see, Chuck hates the periodic table, as he only recognises the element of surprise.

This might not make much sense if you've no idea who Chuck is, so you'd better google him. That still might not help much, mind.

anyone for table tennis?

Look what finally arrived today.

Ten boxes. 1440 of the little rascals.

I feel an explosion coming on.

pimp my ride

schools' analyst competition

Turton took a team out to compete in the North West Heat of the RSC Schools' Analyst Competition held at Manchester Metropolitan University today, where hard work and dedication was rewarded with a third place finish amongst some distinguished company.

The team of lower sixth students was made up from three outstanding candidates from the first year Chemistry course, Aimie Bowles, Christina Long and Tom Waite, who were ready to go head to head with 23 other schools and colleges from the Manchester area in a series of analytical practicals in the high spec. university labs.

An early registration at the University and a brief introductory talk from the organisers gave our intrepid trio a chance to weigh up the opposition, mainly consisting of local rivals and be-suited public schoolboys, after which they were whisked off to the labs to pit themselves against some of the greatest chemical minds in the North West. Mr Smith retired to the pub.

What followed was a whirlwind of analytical procedures, including titrations with multiple indicators, flame photometry, infra red spectroscopy and other qualitative testing for dissolved ions.  

Despite a late wobble with one of the simpler ion identifications, their analytical work had clearly caught the eye of the marking committee, with the University judges awarding them a score of 71 out of a possible 100, good enough for a clear 3rd place overall and a gift voucher which more than covered their lunchtime visit to Aimie's second home, Nandos. Rumours of a rival school being thrown out of the competition for fielding a candidate clearly on performance enhancing hormone replacement therapy were reported to be wide of the mark.

biomedicine afternoon at salford university

A number of Year 12 students had an afternoon out at Salford University today, where they discovered more about the type of research conducted at the University, in addition to getting involved in some practical sessions in the labs. Tom had been here before of course, squeezing crabs and such like, and was on first name terms with all the lecturers. He even knew where to find the bin.

The lab activities involved firstly preparing blood samples to spin in a centrifuge in order to separate out red and white blood cells, along with plasma, to assess blood parameters as an indicator of health. A second activity allowed students to gain an understanding of processing tissue samples for microscope analysis, involving dehydrating a biological sample with alcohol and impregnating it with wax. This was to aid the slicing of the sample into cross sections before staining. The poor little fly.

Students then got the opportunity to see some of the spectroscopy equipment in action, with infra-red and nmr machines being demonstrated, followed by a final talk from some past research students discussing available work placements and other opportunities.

Best of all though, there was chocolate. Lots of chocolate.

UK thalidomide survivors get new grant

The government announced today that a new pot of money has been put aside to help Thalidomide survivors in the UK. It is though that this will be used towards meeting their health needs into their old age, after previous grants have been used to adapt homes and fund the primary care of Thalidomide victims.

New £80 million grant for thalidomide survivors

As you may know already, the drug was dispensed as a morning sickness suppressant in the late 1950's and early 1960's before concerns were raised about an unusual spate of birth defects. Thalidomide has strong sedative properties and many women in the early weeks of pregnancy had taken it to ease their morning sickness, utterly unaware that its effect on the unborn child could be teratogenic (it interfered with embryonic development). The drug was withdrawn in 1961, but not before almost 10,000 babies were affected, often born with shortened, missing or mutated limbs, many of whom were too badly damaged to survive for long. Despite this, it took the makers of the drug over 50 years to make a formal apology.

Thalidomide maker issues apology

Research into Thalidomide and its uses continues today, and it has been proven to be effective in the treatment of certain cancers and leprosy, but the fact that it causes birth defects means that for women its use remains risky and controversial.

What happened to the Thalidomide babies?

Thalidomide has just one chiral atom and so exists as two enantiomers (see diagram above). Notice that two of the groups attached to the chiral centre are part of the same ring structure. They are classified as two different groups, since moving around from the chiral centre the order of atoms is different each way. Laboratory tests after the Thalidomide disaster showed that in some animals the 'S' enantiomer was teratogenic but the 'R' isomer was an effective sedative. It is now known that even when a stereo selective sample of Thalidomide (only one of the optical isomers) is created, enzymes in the body will convert it into a racemic mixture. The means that both enantiomers are formed in a roughly equal mix in the blood. At the time Thalidomide was dispensed as a racemic medication, but even if a drug of only the 'R' isomer had been created, the disaster would not have been averted. 

christmas warning

Now, I don't want to get technical or anything either, but alcohol isn't a solution kids. Ethanol, in its pure form, is a liquid compound. However, if we drank it like that we would most probably go blind and very quickly need another liver.

I guess the board is correct in some respects though, since the ethanol content in most alcoholic beverages varies from 4 or 5% for your typical beers, about 12% for wine, up to 40% for spirits like whiskey and brandy. And then there's absinthe, that mental people drink. The rest is made up of mainly water and assorted flavourings and other dissolved chemicals, thereby making alcoholic drinks the aforementioned 'solution'.

Thanks to Aidan Scarby for sending me the picture.

scottish firework accident

A display in Scotland went wrong on Bonfire Night after a stray rocket set off over £1000 pounds worth of remaining unused fireworks. Check out the video on the link below.

freak firework accident

Luckily no-one was seriously hurt in the ensuing mayhem, although there was a report of minor damage to a local haggis. Mel Gibson was unavailable for comment.

liquid nitrogen cocktails

 

Looks exciting, but one young girl nearly paid with her life at the weekend after drinking a cocktail containing liquid nitrogen whilst out celebrating her 18th birthday. The phenomenon is becoming increasingly popular in trendy bars but the incident that led to her stomach being removed in an emergency procedure has raised issues over the wisdom of such behaviour.

The girl was with friends at Oscar's wine bar in Lancaster city centre when she began to feel ill, becoming breathless and developing severe stomach pain. She was taken to hospital where she was diagnosed with a perforated stomach and surgeons operated immediately to save her life. Lancashire police said: "Medical opinion is that this would have proved fatal had the operation not been carried out urgently." Doctors stated that they had no option but to remove her entire stomach.

An investigation is taking place into the circumstances of how she was given the drink. Once added to alcohol, liquid nitrogen makes the drink appear surrounded by a cloud of white or grey vapour as the liquid boils. In a statement, Oscar's wine bar said it was "tremendously concerned" about the girl and sent its best wishes to her family. Last month, the bar posted a photograph on its Facebook page of a cocktail which contained liquid nitrogen and champagne, and was being sold for £8.95.

Police said the bar had ceased selling all liquid nitrogen cocktails following the incident and had co-operated with all the agencies. The investigation is in its early stages and officers are still interviewing witnesses to establish the facts. Liquid nitrogen, which boils at −196 °C, has become common as a method for flash freezing food or drinks and creating a dramatic vapour cloud. It is stored and transported in vacuum flasks, but can cause severe internal damage if it is ingested.

bbc news report

the dark side of liquid nitrogen cocktails

fuels

Messing about with Year 10 for our C1 module, all about the atmosphere and fuels. A couple of good fuels here, firstly hydrogen. Very explosive, which in addition to it being a gas makes transport and storage of the fuel a challenge. However, the combustion of hydrogen results in no carbon emissions, with the only product of the reaction being water.

2 H₂  +  O₂   →  2 H₂O

Secondly methanol, a very flammable alcohol. Alcohols have the distinct advantage of being renewable fuels which can be produced from the fermentation of sugars or biomass. This means that although they will still produce carbon dioxide as they burn, they are a much more sustainable form of energy when compared to traditional fossil fuels such as coal, oil and gas.

2 CH₃OH  +  3 O₂  →  2 CO₂  +  4 H₂O

Thanks to Josh for sending both videos in.

ping pong

You may have seen the video (elsewhere on this site) of me using liquid nitrogen to make a rather crude bomb from a plastic bottle and a bin full of water. In fact, I may have even demonstrated it live for you on the all weather pitch.

However, in the video below a Plymouth University Professor has had a fine idea and has taken it one step further.

I'm now saving up for 1500 ping pong balls.

the history of molecules

Here's a link to a new part of the RSC website that Mr Bach put me on to. It's a set of short podcasts that gives a brief history of some well known, and in many cases controversial compounds, eg. TNT, nitrous oxide, kevlar and many recreational drugs such as cocaine and LSD.

history of molecules 

Each week a leading scientist or author tells the story behind a different compound or molecule.

They can be played online or downloaded as podcasts. And they're pretty good.


The RSC have a similar set of podcasts for the elements in the periodic table as well.

history of elements 

13A class photo

Thanks to Holly for sending the photo in. One are two of the group were unsurprisingly absent for this which is a bit of a shame but not any real surprise (I'm talking to you Moosa and friends), but I guess you get what you deserve in the end. I also pleased to report that three of you pictured here also scored higher than Maria Imran on your CHEM5 paper, and she well needs to get out more as I've told her on numerous occasions. Congratulations.

Thanks for the good company and (mainly) hard work. It's been a pleasure. Best of luck for the future.

redox equilibria

If you need some answers for the predicting redox reactions worksheet you have used in class you can find them here.

predicting redox reactions worksheet

predicting redox reactions answers

Interview Tips

Found this on the website for the Chemistry Department at the University of York, a well respected Chemistry provider which has regularly been placed highly in national press top university polls. Thought it might give prospective undergraduates a bit of an insight into what to expect from the interview process.

The Times Good University Guide 2012

1. Cambridge
2. Oxford
3. Durham
4. York
5. St Andrews


A Typical Interview

Interviewers typically start by asking you specific questions about your personal statement (for example, your interest in a particular area of Chemistry, including practical work) and your reasons for applying to York, before moving on to more open-ended questions about the study of Chemistry.

We are looking primarily for skills and to assess your potential to do well at York. To help you perform at your best, we suggest that you read through your UCAS personal statement, think over what you’ve studied in Chemistry so far and what has particularly interested you.

It might also be useful for you to practice explaining why you are so passionate about Chemistry that you want to study it to degree level, and why you have applied to York. The importance of being enthusiastic cannot be underestimated!

Consider preparing some things that you would like to tell us, and also think about some questions (either course specific and/or more general questions about student life) you would like to ask us.

nitrogen triiodide

Strike day, and a bit of free time to play around with some home made explosives.

Nitrogen triiodide is worryingly easy to make, and extremely unstable. It is a contact explosive when dry, and produces a beautiful plume of iodine vapour mixed with nitrogen gas when detonated.



As you can see and hear from the video, the explosion is fairly impressive given the small quantity used. You can see that the metre ruler suffers for its art, and you may just be able to make out Mr Chivers' exclamation from his nearby office just as it goes off.

Anyone interested in why it's so unstable will need to consider the entropy change for the reaction.

2 NI₃ (s) → N₂ (g) + 3 I₂ (g)

The large increase in the number of moles from left to right, in addition to the production of gases from a solid, leads to an enormous increase in entropy. Also, the reaction is clearly exothermic. These two factors are ideal for giving a negative free energy change for the reaction, indicating a highly likely, spontaneous reaction.

january 2011 past papers

Summer exams are nearly with us, so you'll need to make sure you are up to date with past papers.

You can find anything up to and including June 2010 papers and mark schemes on the AQA website. Just follow the link in the green box on the right.

However, if you want access to Jan 2011 papers you'll have to download them from the links below. I've included CHEM 1 and CHEM 4 papers for anyone resitting.

CHEM1 paper
CHEM1 mark scheme

CHEM2 paper
CHEM2 mark scheme

CHEM4 paper
CHEM4 mark scheme

CHEM5 paper
CHEM5 mark scheme

Don't forget to pop in for some help if you need it while you are on study leave, and the very best of luck.