Chapter 4 Chem

When the coefficient "4" precedes the reactant NaCIO3 in a balanced chemical equation, there are ____ atoms.

12

Match each compound correctly to its molar mass: CCI4 = CH20 = SF6 = KrF2 =

153.8 g/mol 30.03 g/mol 146.1 g/mol 121.8 g/mol

The number of entities in a mole (to r significant figures) is equal to ______ x 10^23 and is called _____ number.

6.022 avogadro's

What information is contained in a chemical formula?

The identity of the elements present in a substance The relative number of each type of atom

What is a formula unit?

The smallest collection of atoms that represents a substance

The conversation of potassium chlorate to potassium chloride and oxygen is an example of a _____ change.

chemical

The amount of product that is formed from a reactant mixture is determined by the number of moles of the _____ reactant(s).

limiting

The term mole is abbreviated as _____.

mol

For an element, the mass of Avogadrio's number of atoms is known as the ____ mass.

molar

Given the balanced chemical equation 2H2(g) + O2(g) > 2H2O(g), two moles of hydrogen react with ____ mole(s) of oxygen to generate ____ mole(s) of water.

one two

The new substances that are formed in a chemical reaction are called _____.

products

Ions that appear the same on both sides of an ionic equation and are canceled in writing a new ionic equation are called ____ ions.

spectator

The molecular mass of a compound is the ____ of the atomic masses of the elements in one ____ of the compound.

sum molecule

Which of the following actions are permitted in balancing a chemical equation.

Multiplying all coefficients by a common factor Inserting coefficients before the formulas of reactants and products.

Correctly order the steps necessary to balance a chemical equation:

1. Count the number of moles of each atom on each side of the equation 2. Determine the elements that are not balanced 3. Use coefficients to balance one element at a time 4. Do a final check to make sure the equation is balanced

Order the steps for writing a precipitation reaction as a net ionic equation, beginning with the first.

1. Write a balanced molecular equation, using solubility rules to identify any precipitates 2. Write an ionic equation that shows all water-soluble reaction components as free ions 3. Identify and cancel any ions that appear on both sides of the equation 4. Check to ensure that all atoms and charges are balanced

Which of the following can never be done when balancing a chemical equation?

Change the subscripts in a formula of a reactant or product

Which of the following are included in a complete balanced chemical equation?

Coefficients physical states products reaction arrow reactants