Chemistry

What eventually happens to a gas if its pressure is increased?

Topic : State Of Matter

• It condenses

• It evaporates

• It melts

Which of the following processes is endothermic?

Topic : Chemical Reaction

• Bonds being broken in the reactants

• Bonds being made in the products

• Any combustion reaction

What term is given to a reaction which transfers heat energy to the surroundings?

Topic : Chemical reaction

• Endothermic

• Reversible

• Exothermic

If the energy change on an energy level diagram is negative, what does this tell you about the reaction?

Topic : Chemical reaction

• It is endothermic

• Nothing

• It is exothermic

On a reaction profile, what does the height of the hump represent?

Topic : Chemical reaction

• The activation energy

• The energy change

• The energy released when new bonds are made

Which word best describes magnesium oxide?

Topic : Oxide

• Acid

• Fuel

• Base

Hydrogen reacts with oxygen to produce water: H2 + 2O2 → 2H2O. What is the maximum mass of oxygen that will react with 6.0 g of hydrogen? (Relative formula masses: H2 = 2.0, O2 = 32.0)

Topic: Avogadro constant

• 48.0 g

• 64.0 g

• 96.0 g

In a reaction, 1.0 mol of copper reacts with 0.25 mol of oxygen to form 0.50 mol of copper oxide. What is a correct balanced equation for this reaction?

Topic : Avogadro constant

• 4Cu + O2 → 2Cu2O

• 4Cu + 2O2 → 4CuO

• Cu + O2 → CuO2

What is the mass of one silicon atom (relative atomic mass = 28.1)?

Topic : Avogadro constant

• 1.692 × 10-21 g

• 2.143 × 1022 g

• 4.666 × 10-23 g

Which statement about a dynamic equilibrium is correct?

Topic : Chemical equilibrium

• It happens only in a closed system

• It happens only in a non-enclosed system

• It happens in closed and non-enclosed systems