Junior Cert Chemistry: Separating Mixtures

______________ is a substance which cannot be broken down into simpler substances by chemical means.

• An element

• A compound

• A mixture

• A solution

______________ is a substance which is made up of two or more elements which are chemically combined.

• An element

• A compound

• A mixture

• A solution

______________ consists of two or more different substances mingled with each other but not chemically combined.

• An element

• A compound

• A mixture

• A solution

Which of the following are compounds?

• Ammonium nitrate

• Iron Oxide

• Molecular hydrogen

• Calcium hydride

Which of the following are compounds?

• Sodium oxide

• Potassium nitrate

• Rubidium fluoride

• Magnesium chloride

Which of the following are mixtures?

• Sand in water

• Salt in water

• Sodium metal in water

• Magnesium ribbon in hydrochloric acid

A molecule of table sugar (sucrose) may be represented as C₁₂H₂₂O₁₁. What elements are present in table sugar?

• Carbon, Hydrogen, Nitrogen

• Carbon, Hydrogen, Oxygen

• Carbon, Hydrogen, Iodine

• Carbon, Hydrogen, Sulfur

How many atoms are in the compound ammonia, NH₃?

How many atoms are in the compound benzene, C₆H₆?

How many atoms are in the compound methane, CH₄?