National 5 Chemistry Unit 1

How can the rate of reaction be increased?

• By decreasing the temperature

• By decreasing the concentration of reactant

• By increasing the particle size

• Through the use of a catalyst

If 20cm³ of gas is given off in 50 seconds, what is the rate of reaction?

• 0.4 cm³s^-1

• 2.5 cm³s^-1

• 0.4 cm^-3s

• 2.5 cm^-3s

Which is not true about catalysts?

• Speed up chemical reactions

• Are used up during the reaction

• Enable reactions to occur at lower temperatures

• Can be recovered chemically unchanged at the end of the reaction

Which of the following is a non-metal element?

• Calcium

• Phosphorus

• Nickel

• Tin

Which of the following does not belong in the same group as the other three?

• Bromine

• Iodine

• Chlorine

• Argon

Which of the following is not true about elements in the same group?

• They share the same valency

• They have similar chemical properties

• They have the same number of occupied outer energy levels

• They have the same number of electrons in their outer energy level

Which of the following is not true about the electron arrangement of a magnesium atom?

• A magnesium atom has three occupied energy levels

• A magnesium atom has two electrons in the outer energy level

• A magnesium atom has the electron arrangement 2,8,2

• A magnesium atom has a complete outer energy level

Which of the following is false about a proton?

• Has a one positive charge

• Has an approximate mass of 1 atomic mass unit

• Orbits the nucleus

• Has approximately the same mass as a neutron

What is the mass number equal to?

• The number of protons in an atom

• The atomic number

• The number of protons added to the number of neutrons

• The number of protons added to the number of electrons

What are isotopes?

• Atoms with the same number of protons but different numbers of neutrons

• Atoms with the same number of protons and electrons

• Atoms with the same number of neutrons but different numbers of protons

• Atoms with the same mass number but different atomic numbers