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Grace (Student) October 18 2016
Lisa (Parent) August 22 2016
This is quite a complicated sounding question but it is actually quite simple if you break it down! Start by writing a balanced equation for the reaction:
3H2 (g) + N2 (g) => 2NH3 (g)
Now you can see there is four molecules on the left and two on the right, which will help with the answer. It is a good habit to always write your state symbols, especially when this question mentions pressures.
Remember causing a change in the conditions of an equilibrium results in changes to get the equilibrium back to normal.
a) An increase in pressure will cause the amount of product to increase. The equilibrium will shift to the right where there are fewer molecules in order to counteract the change, and decrease the pressure.
b) The reaction is exothermic, which means it has a negative enthalpy change, ie it gives out heat. The amount of product will decrease. The equilibrium will move to the left in the endothermic direction in order to cool the reaction, so less ammonia is produced.
c) This is a bit of a trick question! Think about it: a catalyst basically speeds up a reaction. If the reaction is at equilibrium, the catalyst will simply speed up the reaction in both directions, and not have an affect on the amount of product formed, but just cause the product to be formed more quickly.see more
Break this question down into the four stages: primary, secondary, tertiary and quarternary and for each one describe the structure and what the non-covelant interactions are that hold the protein together. Make sure your sentences are clear and concise, not waffley!
There are four stages of protein folding, primary, secondary, tertiary and quarternary.
The primary structure is the sequence of amino acids held together by peptide bonds
The secondary structure is the protein beginning to fold up. It can have two types of structure: the alpha helix, a coil shape held by hydrogen bonds in the same direction as the coil. The beta pleated sheet is an S shape pattern, also with hydrogen bonds holding the structure together. The hydrogen bonds are between NH and CO groups on the peptides.
The tertiary structure is the protein folded into its precise 3D structure, relating to the functon. This is held together by a range of non-covelant interactions between side groups, including ionic interations, disuplhide bridges, hydrophobic interactions, Van der Waals forces and hydrogen bonds.
The quarternary structure is when single peptides bond to other peptides, for example in haemoglobin.see more
This might be hard at first, but if you work through step by step you'll get there!
Start by getting rid of the fraction, multiply both sides by (3x-1) to get y(3x-1) = 2(1+x)
Multiply out the brackets: 3yx-y = 2+2x. The 3yx might seem hard to sort out but leave it for the moment and it can be factorised and sorted at the end!
Put the x terms on one side (including 3yx) and the non x terms on the other: 3yx-2x = 2+y
Factorise the left side to get a single x term multiplied by everything else: x(3y-2) = 2+y
Then you simply divide both sides by (3y-2) to get
x = (2+y)/(3y-2) and thats your final answer.see more