CHM 130 Lesson 7; Chemical Reactions

Predict the products of the following reactants. Balance the equations: Ca + S → HBr → KI + Cl2 → CuCl2 + Na2S → C2H4 + O2 →

Ca + S --> CaS Her --> H2 + Br2 2Kl + Cl2 --> 2KCl + I2 CuCl2 + Na2S --> CuS + 2NaCl C2H4 + 3O2 --> 2CO2 + 2H2O

Write a balanced equation using the formulas for each of the following reactions: Solid calcium carbonate decomposes to produce solid calcium oxide and carbon dioxide gas Nitrogen monoxide gas reacts with carbon monoxide gas to produce nitrogen gas and carbon dioxide gas Iron metal reacts with solid sulfur to produce solid iron(III) sulfide.

CaCO3 --> CaO + CO2 2NO + 2CO --> N2 + 2CO2 2Fe + 35 --> Fe2S3

Balance the following reaction: __Fe2O3 + __CO → __Fe + __CO2

Fe2O3 + 3CO --> 2Fe + 3CO2

What are the coefficients in the equation: Fe + O2 → Fe2O3 a. 4, 3, 2 b. 1, 2, 3 c. 2, 1, 1 d. 3, 2, 1

a. 4, 3, 2

Identify the following as chemical or physical changes: a) bleaching a pink shirt back to white b) tearing a piece of paper c) burning a log of wood

a. chemical b. physical c. chemical

What type of reaction is each of the following: a) Li3N → Li + N2 b) Mg + N2 → Mg3N2 c) C2H22+ O2 → CO2 + H2O

a. decomposition b. combination c. combustion

How many kJ of energy are released when 41.7 grams CH3OH is burned? 2CH3OH + 3O2 → 2CO2 + 4H2O ΔH = -726 kJ

-472 kJ

Methanol (CH3OH), which is used as a cooking fuel, undergoes combustion to produce carbon dioxide and water: 2CH3OH(g) + 3O2(g) → 2CO2(g) + 4H2O(l)ΔH = -726 kJ How many kilojoules are released when 75.0 g methanol is burned?

-850 kJ

State the number of atoms of each element on the reactant and the product sides of the following equations: CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) 4P(s) + 5O2(g) → P4O10(s) 4NH3(g) + 6NO(g) → 5N2(g) + 6H2O(g)

1 atom C, 4 atoms H, 4 atoms O on each side 4 atoms P, 10 atoms O 4 atoms N, 12 atoms H, 6 atoms N, 6 atoms O

Balance the following equations: Ca(s) + Br2(l) → CaBr2(s) P4(s) + O2(g) → P4O10(s) C4H8(g) + O2(g) → CO2(g) + H2O(l) Sb2S3(s) + HCl(aq) → SbCl3(s) + H2S(g) Fe2O3(s) + C(s) → Fe(s) + CO(g)

Ca (s) + Br2(1) --> CaBr2(s) P4(s) + 5O2 (g) --> P4O10(s) C4H8(g) + 6O2(g) --> 4CO2(g) + 4H2O(g) Sb2S3(s) + 6HCl(aq) --> 2SbCl3(s) + 3H2S(g) Fe2O3(s) + 3C(s) --> 2Fe(s) + 3CO(g)

A reaction that gains energy during the reaction is called a. exothermic b. absorbing c. endothermic d. releasing

c. endothermic

In the reaction, H2 + O2 → H2O, what is the reactant? a. H2 b. O2 c. H2O d. both a and b e. all of the above

d.

Classify each of the following reactions as a combination, decomposition, single replacement, double replacement, or combustion reactions: CuO(s) + 2HCl(aq) → CuCl2(aq) + H2O(l) 2Al(s) + 3Br2(g) → 2AlBr3(s) 2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O Pb(NO3)2(aq) + 2NaCl(aq) → PbCl2(s) + 2NaNO3(aq) 2Mg(s) + O2(g) → 2MgO(s) C6H12O6(aq) → 2C2H6O(aq) + CO2(g)

double replacement combination combustion double replacement combination decomposition

Classify each of the following as exothermic or endothermic reactions: The energy level of the products is lower than the reactants In the body, the synthesis of proteins requires energy 125 kJ is absorbed

exothermic endothermic endothermic

Classify each of the following as exothermic or endothermic: C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g) + 2220 kJ 2Na(s) + Cl2(g) → 2NaCl(s) + 819 kJ PCl5(g) + 67 kJ → PCl3(g) + Cl2(g)

exothermic exothermic endothermic

Determine whether each of the following equations is balanced or not balanced: PCl3(l) + Cl2(g) → PCl5(s) CO(g) + 2H2(g) → CH3OH(l) 2KClO3(s) → 2KCl(s) + O2(g)

yes its balanced yes its balanced no oxygens are not balanced