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How do i solve two linear simultaneous equations 2x+y=7 & 3x-y=8 ?

To start with, try and spot whether or not two of the coeffecients (numbers next to the letters) are the same for either question (i.e. could be a 3x in one equation and a 3x in the other). This also works i...
TB
Answered by Tom B. • Maths tutor
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Briefly discuss Le Chatelier's Principle. Ammonia is made in the Haber Process (3H2(g) + N2(g)<-> 2NH3(g)). Using Le Chetelier's Principal, what happens to the equilibrium yield of ammonia when...: A) Temp increases, B) Press increases C) Catalyst changes

Le Chetelier's Principal gives us a guide to work out what will happen when we change the conditons of a reaction in dynamic equilibrium. It states that if the dynamic equilibiurm is disturbed, the equilibri...
JC
Answered by James C. • Chemistry tutor
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White paint costs £2.80 per litre. Blue Paint costs £3.50 per litre. White paint and blue paint are mixed in the ratio 3:2 Work out the cost of 18 litres of the mixture.

The mixture has a ratio of 3:2, white to blue paint. 3+2=5 so there are 5 parts to the mixture, 3 white and 2 blue. We know the cost of 1 litre of each, so first we can work out the cost of 1 litre of the mi...
HB
Answered by Henry B. • Maths tutor
8373 Views

Explain why an atom has no overall charge.

An atom is comprised of protons, neutrons, and electrons. Protons have positive charge and the number of protons is dictated by the proton number, which is the same as the number of electrons, which have neg...
JC
Answered by James C. • Chemistry tutor
23042 Views

Write down the equation for the Gibbs Free Energy change of a reaction. Hence explain why, for a spontaneous endothermic reaction, there must be an increase in the total entropy.

Gibbs Free Energy change: (delta)G = (delta)H - T(delta)S For a spontaneous chemical reaction, (delta)G must be negative. An endothermic reaction has a positive (delta)H value therefore, in order for the rea...
JC
Answered by James C. • Chemistry tutor
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