Chemistry Test Practice

Which of the following is/are a characteristics of compounds? -- definite composition, combined physically, pure substance, heterogeneous, 1&3

1&3

Four liquids have the following densities A) 1.0 g/ml B) 0.8 g/ml C) 0.6 g/ml D)1.2 g/ml In what order would the liquids form layers from top to bottom if they were carefully placed in a container

CBAD

which is a mixture? -- nickel, air, oxygen, salt, none of these

air

which of the following mixtures is homogeneous? -- salt water, iron and sulfur, salt and sugar, stainless steel, all are homogeneous

all are homogeneous

which does not belong? -- boiling, melting, freezing, burning, none of these

burning

a new substance is formed as a result of a

chemical change

pure substances made of more than one element are called

compounds

an example of a chemical change is the -- corrosions of metals, freezing of milk, dissolving of sugar, none of these

corrosions of metals

lead ways 11.34 grams per cubic centimeter. this statement represents leads

density

air is a mixture because it -- is colorless, is odorless, does not have a inform composition, can be compressed

does not have a uniform composition

chemical changes always involve

either the absorption or liberation of energy

Which of the following is a chemical change? -- evaporation of water, distillation of water, freezing of water, electrolysis of water

electrolysis of water

which of the following is most likely to be malleable? -- gold, hydrogen, sulfur, radon, lead bromide

gold

A chemical change always results characteristically in a change of

identity

which of the following is true of a chemical and physical change but not nuclear change? -- irreversible mass conserved, change of color, formed in any proportions, exothermic

mass conserved

A material that is made up of more than one kind of atom -- cannot be a compound, an element, may be a mixture, must be a hydrate, none of these

may be a mixture

which of the following is a heterogeneous mixture? -- mayonnaise, sea water, pepsi, slat

mayonnaise

An example of an element is -- air, milk, mercury, slat, none of these

mercury

chemical changes differ from physical changes because in chemical changes

new substances are formed

when elements combine chemically they always form -- new elements, atoms, gases, mixtures, none of these

none of these

three different observers measure the melting temperature of a substance and agree on the same value, but the value they obtain does not agree with the accepted value. their measurements can be described as

precise but not accurate

solids differ from liquids in that only samples of solids normally have definite

shapes

one physical property of sugar is its

solubility

which of the following is not a chemical change? -- the dissolving of zinc by HC1, the exploding of gasoline, the corroding of a copper roof, the boiling of water

the boiling of water

which is an element? -- zinc, hydrochloric acid, salt, water, 1&3

zinc