What is the decrease in volume of air when pyrogallol is shaken with 30.00cm³ of air ?

• A. 15.00cm³
• B. 6.30cm³
• C. 0.63cm³
• D. 0.06cm³

The pressure exerted by a sample of a gas confined in 5.86dm³ container at 200C is 4.1atm. What is the number of moles of the gas in the sample? [R = 0.082dm³ atm mol^_1K^_1]

• A) 1.00
• B) 2.00
• C) 3.00
• D) 4.00

A gaseous metallic chloride MCl_x consists of 20.22% of M by mass. The formula of the chloride is [M = 27, Cl = 35.5]

• A. MCl
• B. MCl₂
• C. MCl₃
• D. M₂Cl₆

50cm 3 of a saturated solution of potassium trioxonitrate (V)at 40°C contains 5.05g of the salt. What is the solubility of potassium trioxonitrate (V) at 40°C? (KNO3 = 101)

• A. 1.0 mol/dm³
• B. 1.5mol/dm³
• C. 2.0mol/dm³
• D. 2.5mol/dm³

Carbon is often deposited in the exhaust-pipe of cars because of the

• A. presence of carbon in petrol
• B. dehydrogenation of petrol
• C. incomplete combustion of petrol
• D. presence of additives in petrol

The conditions necessary for the extraction of a water molecule from two molecules of ethanol are

• A. less acid and lower temperature
• B. excess acid and a lower temperature
• C. excess acid and a higher temperature
• D. less acid and a higher temperature

Which is a property of a reaction that has reached equilibrium?

• A) The amount of products is greater than the amount of reactants
• B) The amount of products is equal to the amount of reactants
• C) The rate of the forward reaction is greater than the rate of the reverse reaction
• D) The rate of the forward reaction is equal to the rate of the reverse reaction

When a solution of silver (I) nitrate is saturated with hydrogen sulphide, a black precipitate forms, which is

• A) H₂S
• B) Ag₂S
• C) PbS
• D) HNO₃

If the volume of a given mass of gas at 0°C is 27.3cm3, what will be the volume of the gas at 10°C, pressure remaining constant?

• A. 2.73cm³
• B. 28.3cm³
• C. 37.3cm³
• D. 273cm³

The pressure on 100cm³ of oxygen gas at 35°C is 750mm of Hg. What would be the volume of the gas if the pressure is increased to 1000mm of Hg without changing the temperature?

• A) 133.3cm³
• B) 85cm³
• C) 75cm³
• D) 65cm³