Unit 4: Chemical Reactions

Which describes an oxidation-reduction reaction?

If 5.00 g of NaCl (molar mass 58.44 g/mol) are dissolved in water to make 250.0 mL of solution, what is the molarity? Round to 3 decimal places.

When the equation _Fe + _O₂ → _Fe₂O₃ is balanced, the coefficients are

In a reaction between 10.0 g of hydrogen gas (H₂) and 10.0 g of oxygen gas (O₂), the limiting reactant is

A 0.500 g sample of an unknown metal reacts with excess hydrochloric acid to produce 224 mL of H₂ gas at STP. Given the equation M + 2HCl → MCl₂ + H₂, the molar mass of the metal is approximately

In the net ionic equation for the reaction between aqueous sodium hydroxide and aqueous hydrochloric acid, the spectator ions are

Which of the following is an oxidation-reduction (redox) reaction?

A student performs a gravimetric analysis by adding excess BaCl₂ to 50.0 mL of a Na₂SO₄ solution. The resulting BaSO₄ precipitate, after filtering and drying, has a mass of 1.165 g. The concentration of Na₂SO₄ in the original solution is

In the reaction 2KMnO₄ + 16HCl → 2KCl + 2MnCl₂ + 5Cl₂ + 8H₂O, the oxidation state of Mn changes from

What volume of 0.250 M HCl is needed to neutralize 25.0 mL of 0.100 M NaOH?

In the reaction Mg(s) + 2HCl(aq) → MgCl₂(aq) + H₂(g), the substance being oxidized is

A net ionic equation shows:

In a redox reaction, the substance that is oxidized:

The mole concept is useful because it:

The limiting reagent in a reaction is:

Stoichiometry uses mole ratios from balanced equations to:

Gravimetric analysis determines the amount of a substance by:

Spectrophotometry uses Beer's Law to relate:

Percent yield is calculated as:

If 5.00 g of iron reacts with excess O₂, what mass of Fe₂O₃ is produced?