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Explain the trend in first ionization energy down group 2. (3 marks)

The trend in first ionisation energy down a group: DECREASES due to:- Increase in atomic radius as there are more shells- Increased shielding...

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The Haber process is used to produce ammonia. (Insert equation here) Explain the optimum conditions for this reaction and why these may differ from the conditions used in industry.

N₂ (g)+3H₂ (g) ⇋ 2NH₃ (g) ΔH=-92kJmol^-1 (this is the equation for the above question)
According to Le Chatelier's principle, the position of equilibrium w...

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Explain in terms of particles and collisions how concentration, temperature and addition of a catalyst affect the rate of a reaction.

Concentration: the higher the concentration, the more particles in the same volume. The increase in particle numbers causes an increase in particle collisions, so the rate of reaction increases.Temperatur...

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Calculate the pH of a 0.0131 mol dm^-3 solution of calcium hydroxide at 10 degrees centigrade.

Multiply by 2 because calcium hydroxide = Ca(OH)2 so 2 x [OH-] per molecule.[OH-] = 0.0131 x 2 = 0.0262
Insert [OH-] value into the equilibrium equation along with the value of Kw at 10 degrees centi...

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Explain why adding small amounts of acid or base hardly changes the pH of an acidic buffer solution.

An acidic buffer solution is made up of a weak acid (e.g. ethanoic acid) and a salt containing its conjugate base (e.g. sodium ethanoate). It resists pH change via two mechanisms: The fact that the acid i...

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