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State why it is initially unexpected for alkenes to undergo electrophilic addition with bromine. Explain why this reaction does indeed occur.

Bromine exists as Br₂, and since both bromine atoms are identical - their electronegativities identical, - the electron density is distributed evenly across the molecule (it is non-polar, the a...

Answered by Kai C. • Chemistry tutor

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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...

Answered by Emily W. • Chemistry tutor

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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...

Answered by Emily W. • Chemistry tutor

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