Chemical Reactions Test Review

The smallest unit of an element that retains the chemical properties of the element is called...

• a compound

• an atom

• a mixture

A _________ chemical equation has the same number of atoms of each element on each side of the equation.

• balanced

• complex

• simple

Chemical symbols for the elements are usually restricted to one or two letters and...

• both letters are capitalized

• only the first letter is capitalized

• only the second letter is capitalized

In the expression 4 Ca(No3)2 the total number of nitrogen atoms is...

• one

• five

• eight

If a precipitate forms at the bottom of a test tube, you that...

• a physical change took place

• a chemical reaction took place

• no chemical change took place

A chemical reaction that absorbs energy in the form of heat is described as...

• endothermic

• exothermix

• combustion

CaCO3 represents a chemical

• symbol

• formula

• subscript

The only sure evidence for a chemical reaction is...

• the formation of a gas

• a color change

• the production of one or more new substance

A shorter, easier way to show chemical reactions, using symbols instead of words, is called a...

• chemical equation

• chemical formula

• symbol

Anything that has mass and takes up space is called...

• matter

• energy

• heterogeneous