Spring 23-24 Practice Final Exam

In a lab report, students must write out the word equation for

Zn + Pb(NO₃)₂ --> Zn(NO₃)₂ + Pb

What is the correct word equation?

• Zinc and lead nitrate react to form zinc nitrate and lead.

• Zinc and lead (II) nitrate react to form zinc nitrate and lead.

• Zinc and lead nitrogen oxide react to form zinc nitrogen oxide and lead

• Zinc and lead (II) nitrate react to form zinc nitrite and lead (II)

Students perform an experiment that instantaneously forms a precipitate. They mix aqueous iron (III) nitrate and sodium hydroxide to produce iron (III) hydroxide and aqueous sodium nitrate.

What is the correct balanced equation for this reaction to show conservation of mass?

• 3FeNO₃ + 2NaOH → FeOH₃ + 3NaNO₃

• FeN + 3NaOH → FeOH₃ + 3NaN

• Fe(NO₃)₃ + 3NaOH → Fe(OH)₃ + 3NaNO₃

• Fe₃+NO₃^- + Na⁺OH^- → Fe³⁺OH^- + Na⁺NO₃^-

What are the correct coefficients if the law of conservation of mass is applied to the decomposition of solid ammonium nitrite to nitrogen gas and liquid water?

• 2, 2, 2

• 1, 1, 2

• 2, 1, 2

• 1, 2, 2

The reaction between solid aluminum and liquid bromine is exothermic. This reaction creates the product aluminum bromide.

What equation includes the correct formulas and demonstrates conservation of mass?

• Al(s) + Br2(l) → AlBr3(s)

• Al(s) + Br(l) → AlBr(s)

• Al(s) + 3Br(l) → AlBr₃(s)

• 2Al(s) + 3Br₂(l) → 2AlBr₃(s)

Students perform several experiments recording the reactions in lab journals. The students write and balance the chemical equations for each reaction and include the state of matter notations for each compound. The equations are pictured here. Which chemical involved in the student experiments is dissolved in water?

• Fe₂O₃

• Fe

• Mg(OH)₂

• MgO

What are the coefficients that would correctly balance this reaction? 
 

__Ni + __C₄H₈N₂O₂ → __Ni(C₄H₈N₂O₂)₂

• 1, 2, 1

• 2, 2, 1

• 2, 1, 1

• 2, 2, 2

What is the balanced equation for the combustion of magnesium?

• Mg (s) + O₂ (g) → MgO (g)

• Mg (s) + O₂ (g) → MgO₂ (g)

• 2 Mg (s) + O₂ (g) → 2 MgO (s)

• Mg (s) + 2 O₂ (g) → MgO₄^2- (aq)

Which coefficients are required to correctly balance the equation, C₂H₂ + O₂ → CO₂ + H₂O?

• 1, 2, 3, 2

• 2, 5, 4, 2

• 2, 4, 5, 2

• 2, 3, 5, 2

What are the coefficients that would correctly balance this equation? 
 

__Zn + __K₂CrO₄ → __K + __ZnCrO₄

• 2, 1, 2, 1

• 1, 2, 3, 1

• 1, 2, 1, 2 

• 1, 1, 2, 1

When solid zinc is dissolved into a solution of copper sulfate, the reaction creates a clear solution of zinc sulfate. In this oxidation-reduction reaction, the zinc atoms are oxidized, and copper (II) ions are reduced to create solid copper.

What type of reaction occurs between zinc and copper sulfate?

• Acid-Base

• Synthesis

• Decomposition

• Single replacement