Chapter 8 Test

When a solid produced by a chemical reaction separates from the solution it is called

• A precipitate.
• A reactant.
• A molecule.
• The mass of the product.

A chemical equation is balanced when the

• coefficients of the reactants equal the coefficients of the products.
• same number of each kind of atom appears in the reactants and in the products.
• products and reactants are the same chemicals.
• subscripts of the reactants equal the subscripts of the products.

In the chemical equation 2Mg(s) + O₂ (g) → 2MgO(s),

• Mg represents the product magnesium.
• the reaction yields magnesium.
• Mg represents the reactant magnesium.
• O2 represents the product oxygen gas.

You mix solution A with solution B in a beaker. Which of the following observations does not help you prove that a chemical reaction has occurred?

• The beaker becomes warm.
• You see gas bubble out of solution.
• Solution A and solution B when mixed turn yellow.
• None of the above; all help prove that a chemical reaction has occurred.

To balance a chemical equation, you must

• adjust the coefficients.
• adjust the number of products.
• adjust the number of reactants.
• adjust the subscripts.

Which coefficients correctly balance the formula equation below? KClO₃ (s)→ KCl(s) + O₂ (g)

• 1, 1, 1
• 2, 2, 3
• 1, 1, 3
• 2, 1, 1

In which type of reaction do two or more compounds react to form one product?

• synthesis
• decomposition
• combustion
• single-displacement

The formation of an aqueous product in a chemical reaction is represented by the symbol

• (aq).
• (s).
• (g).
• (l).

Which of the following indicates that a chemical equation is balanced?

• The numbers of atoms of each element are the same on both sides of the equation.
• All of the coefficients are the same.
• The numbers of molecules on each side of the equation are equal.
• The sums of the coefficients on each side of the equation are equal.

From a complete and correctly written chemical equation, you can obtain the

• chemical formulas of the reactants and products.
• relative amounts of the reactants and products.
• physical states of the reactants and products.
• All of the answers