HSSC chemistry

The number of protons in a sodium atom is:

• 1 10
• 2 23
• 3 11
• 4 12

The number of electrons in a chloride ion (atomic number 17) is:

• 1 16
• 2 18
• 3 17
• 4 19

Boyle's law relates the pressure of a gas to its:

• 1 Temperature at constant volume
• 2 Density at constant pressure
• 3 Volume at constant temperature
• 4 Mass at constant volume

According to Charles's law, the volume of a fixed mass of gas at constant pressure is proportional to:

• 1 Its pressure
• 2 Its absolute temperature
• 3 Its density
• 4 Its mass

The molar mass of sulfuric acid, H₂SO₄ (H = 1, S = 32, O = 16), is:

• 1 96 g/mol
• 2 82 g/mol
• 3 98 g/mol
• 4 64 g/mol

The number of moles in 4.9 g of sulfuric acid (molar mass 98 g/mol) is:

• 1 5
• 2 0.05
• 3 0.2
• 4 0.5

The empirical formula of glucose, C₆H₁₂O₆, is:

• 1 C₂H₄O₂
• 2 CH₂O
• 3 C₆H₁₂O₆
• 4 C₃H₆O₃

The pH of a 0.001 M solution of hydrochloric acid is:

• 1 11
• 2 3
• 3 1
• 4 0.001

A buffer solution is a mixture of:

• 1 A weak acid and its salt
• 2 Water and a salt
• 3 Two strong acids
• 4 A strong acid and a strong base

A reaction is spontaneous at constant temperature and pressure when:

• 1 ΔG is positive
• 2 ΔG is negative
• 3 ΔH is positive
• 4 ΔS is zero

A reaction has the rate law rate = k[A]². The order of the reaction is:

• 1 Zero
• 2 Third
• 3 First
• 4 Second

In the electrolysis of molten sodium chloride, sodium is formed at the:

• 1 Salt bridge
• 2 Cathode
• 3 Anode
• 4 Electrolyte surface

In an electrochemical cell, oxidation takes place at the:

• 1 Cathode
• 2 Salt bridge
• 3 Voltmeter
• 4 Anode

Which reagent is decolourised by an alkene?

• 1 Copper sulfate solution
• 2 Limewater
• 3 Bromine water
• 4 Litmus solution

The IUPAC name of CH₃CH=CH₂ is:

• 1 Propane
• 2 Propyne
• 3 Propene
• 4 Butene

Ethanol and dimethyl ether, both C₂H₆O, are examples of:

• 1 Functional group isomers
• 2 Optical isomers
• 3 Chain isomers
• 4 Position isomers

Benzene reacts with a mixture of concentrated nitric acid and sulfuric acid to give:

• 1 Chlorobenzene
• 2 Phenol
• 3 Nitrobenzene
• 4 Cyclohexane

Aldehydes can be tested with:

• 1 Litmus paper
• 2 Tollens' reagent
• 3 Limewater
• 4 Bromine water

The hybridisation of the carbon atoms in ethyne (C₂H₂) is:

• 1 sp³d
• 2 sp³
• 3 sp
• 4 sp²

The bond angle in a water molecule is about:

• 1 104.5°
• 2 180°
• 3 109.5°
• 4 120°

The high boiling point of hydrogen fluoride compared with hydrogen chloride is because of:

• 1 A lower molar mass
• 2 Metallic bonding
• 3 Hydrogen bonding
• 4 Ionic bonding

Going down a group of the periodic table, the first ionisation energy usually:

• 1 Decreases
• 2 Stays the same
• 3 Doubles
• 4 Increases

Which of these is a Lewis acid?

• 1 OH⁻
• 2 H₂O
• 3 NH₃
• 4 BF₃

The catalyst used in the Haber process for ammonia is:

• 1 Nickel
• 2 Iron
• 3 Vanadium pentoxide
• 4 Platinum

Which gas is mainly responsible for acid rain?

• 1 Nitrogen
• 2 Sulfur dioxide
• 3 Helium
• 4 Argon