Grade 7 Science – Higher Level Multiple Choice

• Element only

• Compound only

• Compound and molecule

• Element and molecule

Which situation describes the formation of a compound rather than just a molecule?

• Two oxygen atoms bond together

• Two hydrogen atoms bond together

• Hydrogen atoms bond with oxygen atoms to form water

• Several atoms of gold join together

A sample contains only carbon atoms. Which conclusion is correct?

• It must be a compound

• It is an element

• It must contain molecules of different elements

• It cannot form molecules

• It contains only hydrogen atoms

• It contains different elements chemically bonded in a fixed ratio

• It can be separated by filtration

• It is made of identical atoms

Which example shows atoms forming an elemental molecule instead of a compound?

• NaCl

A student states that “all molecules are compounds.” Why is this statement incorrect?

• Compounds contain only one atom

• Molecules cannot contain elements

• Some molecules contain atoms of the same element

• Compounds cannot form molecules

When atoms chemically bond, what changes most significantly?

• The number of protons

• The number of neutrons

• How atoms are connected to form molecules

• The atomic identity of each element

• contains only one atom

• contains atoms that are not bonded

• contains different elements chemically bonded together

• cannot exist as a molecule

A student tries to separate salt dissolved in water using filtration but fails. Why?

• Salt particles are too large

• Filtration only works for gases

• Salt is chemically bonded to water

• Salt is completely dissolved, forming a homogeneous mixture

Which method would best separate iron filings from a mixture of sand and iron?

• Evaporation

• Sieving

• Magnetic separation

• Distillation