IQWST Lesson 1 and 2 Review

Front

Substances with only one type of atom or compound

Back

Pure substance

Answer explanation

A pure substance consists of only one type of atom or molecule, making it distinct from mixtures. Homogeneous and heterogeneous mixtures contain multiple types of substances, while a suspension is a type of heterogeneous mixture.

Front

Definition of a mixture

Back

Two or more substances together, not chemically combined.

Answer explanation

A mixture consists of two or more substances that are physically combined but not chemically bonded. This distinguishes it from pure substances and solutions, making 'mixture' the correct answer.

Front

Mixture with visible components

Back

Heterogeneous mixture

Answer explanation

A heterogeneous mixture is characterized by its non-uniform composition, where individual substances can be seen and detected. This contrasts with homogeneous mixtures, which blend smoothly and are uniform throughout.

Front

Substances mixed well, parts won't separate

Back

Homogeneous mixture

Answer explanation

A homogeneous mixture is one where the components are evenly distributed and cannot be easily separated. In this case, the substances are mixed so well that they form a uniform composition, making 'homogeneous mixture' the correct choice.

Front

Solutions are ___________ mixtures.

Back

Homogenous

Answer explanation

Solutions are homogenous mixtures because their components are uniformly distributed, making them appear as a single phase. This distinguishes them from heterogeneous mixtures, where the components remain separate.

Front

Solubility

Back

Amount of solute dissolved by solvent

Answer explanation

Solubility refers to the maximum amount of solute that can be dissolved in a solvent at a given temperature and pressure. Therefore, the correct choice is 'the amount of solute that can be dissolved by the solvent.'

Front

Oil in water

Back

Insoluble

Answer explanation

Oil is insoluble in water because it is a nonpolar substance, while water is polar. This difference in polarity prevents oil from mixing with water, making 'insoluble' the correct choice.

Front

Two or more atoms combined

Back

Compounds

Answer explanation

Compounds are substances formed when two or more atoms combine chemically. Unlike elements, which consist of a single type of atom, compounds contain different types of atoms bonded together.

Front

The air is a ___________

Back

mixture

Answer explanation

The air is a mixture because it consists of various gases, primarily nitrogen and oxygen, along with trace amounts of other substances. It is not a pure element or compound, making 'mixture' the correct choice.

Front

Elements can be broken down into simpler substances?

Back

False

Answer explanation

Elements are pure substances that cannot be broken down into simpler substances by chemical means. Therefore, the statement is false.