Chemical Reactions Review

How many oxygen atoms are represented by 2Pb(SO4)2?

• 2
• 4
• 8
• 16

A solid produce from two aqueous solution in a chemical reaction is known as a(n)...

• precipitate
• oxide
• salt
• hydrocarbon

Classify the following chemical reaction: HCl(aq) + NaOH(aq) --> NaCl + H₂O(l)

• Double Replacement
• Combustion
• Single Replacement
• Decomposition

Which of the following statements about the reaction below is NOT TRUE? N2 (g) + 3H2(g) ⇌ 2NH3(g) + energy

• It is endothermic
• Overall, it realses energy.
• It is in equilibrium
• It is reversible

To balance a chemical equation, it may be necessary to change the substances’...

• subscripts
• superscrirpts
• coefficients
• formulas

Which of the following statements best describes the following reaction? MgCl2 + I2 --> MgI2 + Cl2

• It's a single replacement reaction
• It is a synthesis reaction
• It is a decomposition reaction
• The reaction will not only occur

Which of the following would not be considered evidence of a chemical reaction?

• Formation of a precipitate
• State of matter change
• Production of a gas
• Sudden release of light

Which of the following statements is true about chemical equilibrium?

• The reaction has reached its end.
• The forward and reverse reactions occur at the same rate.
• The concentration of reactants is higher than the concentration of products.
• The amount of reactants and products is the same.

In a chemical equation, “dissolved in water” is represented by which of the following symbols?

• (s)
• (l)
• (g)
• (aq)

Two students conduct several tests to determine the identity of an unknown metal. They noted that it was powdery white, conducted both heat and electricity, and had a density of 10.49 g/cm3. It did not react with water but, with nitric acid it released a gas. What evidence above supports a chemical change in this unknown?

• It conducts heat.
• It reacts with nitric acid to produce a gas.
• It has a density of 10.49 g/cm3.
• It is powdery white.