4.3

Question 1

reactants

Answer 1

of pure substances (elements and

compounds)

Question 2

products

Answer 2

of pure

substances different then the reactants

Question 3

chemical

reaction

Answer 3

One or more chemical changes that occur at the

same time are called

Question 4

chemical equation

Answer 4

A chemical reaction may be represented using

Question 5

symbolic equation

Answer 5

a set of chemical
symbols and formulas that identify the reactants and products in a
chemical reaction

Question 6

word equation

Answer 6

nitrogen monoxide oxygen ➔ nitrogen dioxid

Question 7

symbolic equation:

Answer 7

2NO(g) O2(g) ➔ 2NO2(g)

Question 8

Coefficients

Answer 8

Integers are placed in front of the formula or a
chemical symbol for an element f NO react with one molecule of O2 to form two
molecules of NO2 . In other words, NO and O2 react in a 2:1 ratio

Question 9

State of matter

Answer 9

Letters indicate the compound’s state: (g) for

gas; () for liquid; (s) for solid; (aq) for aqueous (dissolved in water).

Question 10

conservation of mass

Answer 10

states that mass
is conserved in a chemical reaction; the total mass of the products is
always equal to the total mass of the reactants in a chemical reaction

Question 11

skeleton equation

Answer 11

shows the

formulas of the reactants and products skeleton equation: K O2 ➔ K2O

Question 12

balanced chemical equation:

Answer 12

CH4 2O2 ➔ 2H2O CO