Consider the equilibrium reaction N2 + 3H2 ⇌ 2NH3 Determine the equilibrium constant for this reaction if [N2] = 0.175 mol/L; [H2] = 0.75 mol/L; [NH3] = 0.55 mol/L Give your answer to 4 s.f.

Which one of the following statements about disulfide bonds is true? 

Which one of the following statements about nucleotides and nucleic acids is true? 

Which one of the following species behave as an electrophile? 

Questions 41 – 43 relate to the following problem: A solution of sodium hydroxide contained 0.95 mol dm-3. Using phenolphthalein indicator, titration of 50.0 cm3 of this solution required 27.0 cm3 of a hydrochloric acid solution for complete neutralisation.                                       Question 42: How many moles of hydrochloric acid were neutralised? Give your answer to 4 d.p.

How many moles are there in 84 g of magnesium? (atomic mass 24)    

Are the following molecules likely to be hydrophilic or hydrophobic? [A]     [B]   [C]

What is the pH of an HCl solution at a concentration of 4.68 x 10–4 mol L–1? Give your answer to 2 d.p.

A hydrophobic compound will usually dissolve into an aqueous solvent. True or false? 

Which one of the following statement about enzymes is false?