Covalent Bonding

Explain why compounds formed from non-metals normally do not conduct electricity and have a relatively low boiling point?

Ideal Gas Conditions

Under what conditions of temperature and pressure is the behavior of a real gas most like that of an ideal gas? Explain your answer.

Speed Of Reaction (Concentration)

Explain in molecular terms how the rate of reaction is affected by changing the concentrations of reactants

Buffer

What is the pH of a solution containing 0.10 mol/dm3 Citric Acid and 0.30 mol/dm3 Sodium Citrate? Citric Acid: Ka = 7.4 x 10^-4 mol/dm3

Isotopes

In a sample of 100 atoms of Boron, there are 20 atoms of Boron – 10 and 80 atoms of Boron – 11. (i) Explain why these two forms of Boron are isotopes? (ii) Calculate the relative atomic mass of

Strong Or Weak Acid?

A 0.010 mol/dm3 aqueous solution of an acid HA has a pH of 2.0. Is HA a strong or a weak acid? Explain your answer.

Enthaply Change

Calculate the ∆Hsolution, ∆Ssolution and ∆Gsolution for the following equilibrium at 298K. AgCl (s) <-> Ag+ (aq) + Cl- (aq) AgCl (s): ∆Hf = -127.0 kJ/mol, ∆Sf = +96.1 J/mol Ag+ (aq): ∆Hf = +105.9 kJ/mol, ∆Sf = +73.9 J/mol

Melting Points

Explain, in terms of their structure and bonding, why the melting points of Calcium Fluoride (CaF2 1418°C) and Phosphorus Trifluoride (PF3 -151°C) are so different?

Geometrical Isomerism

How many geometrical isomers are there of hex-2,4-diene, CH3CH=CHCH=CHCH3?

Hydrolysis of Halogenoalkanes

The hydrolysis of 1-chloropropane to produce propan-1-ol is much slower corresponding to hydrolysis of 1-iodopropane. Explain this observation.