Unit 3, Chapter 2 Review Questions

Which of the following is a synthesis reaction?

(2) 2Cu + O2 → 2CuO

Two molecules of hydrogen are represented by

(2) 2H₂

Which of the following reactions will not take place spontaneously? (1) Ca+ AgNO3 (2) Pb + Al(NO3)3 (3) Cr + Pb(NO3)2 (4) Co + HCl

(2) Pb + Al(NO3)3

Consider the following unbalanced equation. 3Fe ₊ 4H2O → 1Fe₃O₄ ₊ 4H₂. When correctly balanced using smallest whole numbers, the sum of the coefficients is

12

Determine the total number of oxygen atoms in the reactants of the balanced equation

16

In an experiment, 2.54 grams of copper completely reacts with sulfur, producing 3.18 grams of copper(I)sulfide. Determine the total mass of the sulfur consumed

3.18-2.54=0.64

Consider the following unbalanced equation. Mg₂Si ₊ HCl → MgCl₂⁺ SiH₄. When the equation is balanced using the smallest whole -number coefficients, the coefficient of HCl is

4

Rust contains Fe₂O₃. Given the balanced equation representing the formation of rust: Fe (s) + O₂ (g) → Fe₂O₃ (s). Balance the equation using the smallest whole-number coefficients

4Fe (s) + 3O₂ (g) → 2Fe₂O₃ (s).

What is the total number of atoms of oxygen in the formula Mg(ClO₄)₂ ∙6H₂O?

8+6 = 14

Given the balanced equation representing a reaction 2H₂ + O₂ → 2H₂O What is the mass of H₂O produced when 10.0 grams of H₂ reacts completely with 80.0 grams of O₂?

80+10=90g

State evidence that a chemical reaction occurred when the tablet was placed in the water.

A gas was formed.

State one observation that indicates that a chemical change has taken place.

CO₂ gas was released when the candle burned.

Which is the correct formula of dichlorine monoxide?

Cl2O

Which of the following is a polyatomic ion?

Cr₂O7₇⁻²

Which formula is correctly paired with its name?

CuCl₂, copper(II) chloride

In an experiment, 2.54 grams of copper completely reacts with sulfur, producing 3.18 grams of copper(I)sulfide. Write the chemical formula of the compound produced

Cu₂S

Balance this equation using the lowest whole-number coefficients.C₆H₁₂O₆ → C₂H₅OH + CO₂

C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂

What is the chemical formula of iron(III) sulfide?

Fe₂S₃

A tablet of one antacid contains citric acid, H₃C₆H₅O₇,and sodium hydrogen carbonate, NaHCO₃. When the tablet dissolves in water, bubbles of CO₂ are produced. This reaction is represented by their complete equation below. H₃C₆H₅O₇(aq) + 3NaHCO₃(aq) → Na₃C₆H₅O₇(aq) + 3CO₂(g) + 3__(l) Complete the equation by writing the missing chemical formula.

H₂O

Which of the following is the formula of a compound?

LiH

Magnesium metal reacts with hydro-chloric acid to produce hydrogen. Balance the equation for the reaction using the lowest whole-number integers. Mg (s) + HCl (aq) → MgCl₂ (aq) + H₂(g)

Magnesium metal reacts with hydro-chloric acid to produce hydrogen. Balance the equation for the reaction using the lowest whole-number integers. Mg (s) + 2HCl (aq) → MgCl₂ (aq) + H₂(g

In an investigation, a drip less wax candle is massed and then lighted. As the candle burns, a small amount of liquid wax forms near the flame. After 10 minutes,the candle's flame is extinguished and the candle is allowed to cool. The cooled candle is massed. Identify one physical change that takes place in this investigation.

Melting

What is the correct formula of nickel(II) oxide?

NiO

What is the IUPAC name for the compound ZnO?

Zinc (II) Oxide

A chemical formula represents

both quantitative and qualitative information

Identify the type of reaction represented in the equation in question 29

decomposition

What is the name of the compound whose formula is N₂O₅?

dinitrogen pentoxide

In an endothermic reaction

energy is a reactant and the surrounding temperature decreases

As an exothermic reaction occurs, the surrounding temperature

increases

Pure oxygen reacts with metals to form

oxides

What type of chemical reaction occurs during this reaction?

single replacement

A reaction in which two substances combine to form a single product is called a

synthesis

Identify the type of reaction represented by this equation

synthesis

An empirical formula represents

the lowest integer ratio of the elements in a compound