A level Chemistry Mixed 1

What pH is the solution formed after sodium reacts with water?

• pH 13-14

• pH 10-11

• pH 7-9

• pH 1-3

What is the correct balanced equation for magnesium reacting with steam, including state symbols?

• Mg(s) + H₂O(g) → MgO(s) + H₂(s)

• Mg(s) + H₂O(g) → MgO(s) + H₂(g)

• Mg(l) + H₂O(g) → MgO(s) + H₂(g)

• Mg(s) + H₂O(g) → MgO(s) + H₂O(g)

What is the name of the mechanism for the reduction of carbonyls?

• Nucleophilic Substitution

• Nucleophilic addition

• Nucleophilic addition-elimination

• Electrophillic addition

Which is the correct balanced redox half equation for the oxidation of iron(ii) to iron(iii)?

• Fe³⁺ ------> Fe²⁺ + e¯

• Fe²⁺ +e- ------> Fe³⁺

• Fe²⁺ ------> Fe³⁺ + 3e¯

• Fe²⁺ ------> Fe³⁺ + e¯

What is the general formula for the acid dissociation constant?

• K_c= [H+][A-]/ [HA]

• K_a= [H+][A-]/ [HA]

• K_a= [HA]/[H+][A-]

• K_a= [H+][A-] x [HA]

Calculate the pH of the following weak acid: 0.200 mol dm^-3 butanoic acid (K_a = 1.51 x 10^-5 mol dm^-3)

• 2.70

• 4.48

• 2.76

• 6.34

What is the typical equivalence point of a strong acid weak base titration?

• 5

• 3

• 2

• 4

What chemical test shows that Benzene molecules do not contain any double bonds?

• It does not decolourise chlorine water.

• It does decolourise bromine water.

• It does not decolourise bromine water.

• It does not decolourise iodine water.

Name this molecule CH₃CH₂COCH₂CH₃

• Ethan-3-one

• pentan-3-al

• pentan-3-one

• pentan-3-ol

What measurement of a substance is the best measure of its purity

• Boiling point

• The flame colour when burned

• Melting point

• Its reaction with oxygen