IB Chemistry HL Cumulative Test #1 Topics 1-4

Assuming that all volumes are measured at the same temperature and pressure and the reaction goes to completion what volume of ammonia, in cm³, can be prepared by reacting 20 cm³ of nitrogen gas with 30 cm³ of hydrogen gas?

N₂(g) + 3H₂(g) → 2NH₃(g)

• 20

• 30

• 40

• 50

When calcium carbonate is heated it decomposes according to the equation:

CaCO₃(s) → CaO(s) + CO₂(g)

When 50 g of calcium carbonate is heated, 7 g of calcium oxide are formed. What is the percentage yield?

• 7%

• 25%

• 50%

• 56%

10 cm³ of carbon monoxide and 10 cm³ of oxygen are mixed together at the same temperature and pressure. What will be the total volume of gas present, in cm³, after they have reacted, assuming that the volume is measured at the same temperature and pressure?

2CO(g) + O₂(g) → 2CO₂(g)

• 10 cm³

• 15 cm³

• 20 cm³

• 25 cm³

Which solution contains 0.2 mol of potassium hydroxide, KOH?

• 1 cm³ of 0.2 mol dm^-3 KOH(aq)

• 10 cm³ of 0.2 mol dm^-3 KOH(aq)

• 100 cm³ of 2.0 mol dm^-3 KOH(aq)

• 1 dm³ of 2.0 mol dm^-3 KOH(aq)

What will be the concentration, in mol dm^-3, of the resulting solution when 200 cm³ of 0.200 mol dm^-3 hydrochloric acid, HCl(aq) are mixed with 300 cm³ of 0.100 mol dm^-3 HCl(aq)?

• 0.14 mol dm^-3

• 0.30 mol dm^-3

• 0.07 mol dm^-3

• 0.15 mol dm^-3

The equation for the complete combustion of methylpropane is

2CH₃CH(CH₃)CH₃(g) + 13O₂(g) → 8CO₂(g) + 10H₂O(l)

What amount, in mol, of carbon dioxide will be formed when three moles of methylpropane (CH₃CH(CH₃)CH₃) are combusted completely?

• 4

• 8

• 12

• 16

Which sample of fluorine gas, F₂, contains the greatest number of fluorine molecules?

(Avogadro’s constant = 6 x 10²³ mol^-1)

• 1.9 x 10²³ F₂ molecules

• 1.9 dm³ of F₂ at 273 K and 1.00 x 10⁵ Pa pressure

• 1.9 g F₂

• 1.9 mol F₂

Which factors explain why a real gas does not behave like an ideal gas at low temperatures and high pressure?

I. The volume occupied by the gaseous molecules is not negligible compared to the volume of the gas.

II. The attractive forces between the molecules affect the pressure exerted by the gas.

III. The kinetic energy of a real gas is different to the kinetic energy of an ideal gas at the same temperature.

• I and II only

• I and III only

• II and III only

• I, II, and III

Which pair of elements reacts most readily?

• Li + Br2

• Li + Cl2

• K + Br2

• K + Cl2

For which element are the group number and the period number the same?

• Li

• Be

• B

• Mg