CHEM1083 - Chapter 5

Combination reaction

A reaction in which two or more reactants are joined to form a single product

Decomposition reaction

A reaction in which a single reactant is converted to two or more products

Single replacement reaction

A reaction in which one element replaces another element in a compound to form a different compound and element as products

Double replacement reaction

A reaction in which two compounds exchange "parts" -- atoms or ions -- to form two new compounds

Write a balanced equation for the reaction of ethane (C2H6) with O2 to form CO2 and H2O.

2 C2H6 + 7O2 --> 4 CO2 + 6 H2O

One term with the chemical equation contained the coefficient 3 in front of the formula Al2(SO4)3. How many atoms of each type of element does this represent

3 Al2(SO4)3 Al - 6 S - 6 O - 15

What is the percent yield of B in a reaction that uses 10.0 g of a starting material A, has a theoretical yield of 12.0 g of B, and an actual yield of 9.0 of B?

75%

Oxidizing agent

A compound that gains electrons causing another compound to be oxidized

Reducing agent

A compound that loses electrons causing another compound to be reduced

Law of conservation of matter

A law that states that atoms cannot be created or destroyed in a chemical reaction

Avogadro's number

A quantity that contains 6.02 x 10^23 items - usually atoms, molecules or ions

Mole

A quantity that contains 6.02 x 10^23 items - usually atoms, molecules, or ions

Redox Reaction

A reaction that involves the transfer of electrons from one element to another

Product

A substance formed in a chemical reaction

The reaction of hydrogen (H2) with acetylene (C2H2) forms ethane (C2H6). Is acetylene oxidized or reduced in this reaction. Explain

Acetylene is reduced because it gains hydrogen atoms

Half reaction

An equation written for an individual oxidation or reduction that shows how many electrons are gained or lost.

Balanced chemical equation

An equation written so that an equal number of atoms of each element is present on both sides

Chemical equation

An expression that uses chemical formulas and other symbols to illustrate what reactants constitute the starting materials in a reaction and what products are formed.

Percent yield

The amount of product actually formed in a particular reaction divided by the theoretical yield, multiplied by 100

Theoretical yield

The amount of product expected from a given amount of reactant based on the coefficients in the balanced chemical equation.

Actual yield

The amount of product formed in a reaction, determined by weighing the product on a balance.

Molecular weight

The formula weight of a covalent compound.

Reduction

The gain of electrons by an atom. Reduction may result i the loss of oxygen atoms or the gain of hydrogen atoms

Oxidation

The loss of electrons from an atom. Oxidation may result in a gain or oxygen atoms or a loss of hydrogen atoms

Molar mass

The mass of one mole of any substance, reported in grams per mole

Limiting reactant

The reactant that is completely used up in a reaction

Reactant

The starting material in a reaction

Formula weight

The sum of the atomic weights of all the atoms in a compound, reported in atomic mass units (AMU)

Zinc - silver oxide batteries are used in cameras and hearing aids. Identify the species that is oxidized and the the species that is reduced in the following redox reaction. Identify the oxidizing agent and the reducing agent Zn + Ag2O --> ZnO + 2Ag

Zn: Oxidized, reducing agent Ag⁺: reduced, oxidizing agent

The local anesthetic ethyl chlorine (C2H5Cl, molar mass 64.51 g/mol) can be prepared by reaction of ethylene (C2H4, molar mass 28.05 g/mol) with HCl (molar mass 36.46g/mol), according to the balanced equation, C2H4 + HCl --> C2H5Cl, a. If 8.00 g of ethylene and 12.0 g of HCl are used, how many moles of each reactant are used? What is the limiting reactant c. How many moles of product are formed d. How many grams of product are formed e. if 10.6 g of product are formed. what is the percent yield of the reaction?

a. 0.285 mol ethylene and 0.329 mol HCl b. ethylene c. 0.285 mol d. 18.4 g e. 57.6%

Which quantity has the greater mass? a. 1 mol of Fe atoms or 1 mol of Sn atoms b. 1 mol of C atoms or 6.02 x 10^23 N atoms c. 1 mol of N atoms or 1 mol of N2 molecules d. 1 mol of CO2 molecules or 3.01 x 10^23 N2O molecules

a. 1 mol Sn b. 602 x 10^23 N atoms c. 1 mol N2 molecules d. 1 mol CO2

How many molecules of butane (c=C4H10) are contained in the following number of moles: a. 2.00 mol b. 0.250 mol c. 26.5 mol d. 222 mol e. 5.00 x 10^5 mol

a. 1.20 x 10 ²⁴ b. 1.51 x 10²³ c. 1.60 x 10²⁵ d. 1.34 x 10²⁶ e. 3.01 x 10²⁵

How many grams are in 5.00 mol of each compound a. HCl b. Na2So4 c. C2H2 D. Al(OH)3

a. 182g b. 710 g c. 130 g d. 390 g

Write the balanced equation for each reaction a. H2 + O2 --> H2O b. NO + O2 --> NO2 c. CH4 + Cl2 --> CH2Cl2 + HCl

a. 2 H2 + O2 --> 2 H2O b. 2NO + O2 --> 2 NO2 c. CH4 + 2 Cl2 --> CH2Cl2 + 2HCl

The reaction of methane (Ch4) with Cl2 forms chloroform (CHCl3) and HCl. CH4(g) + 3 Cl2(g) --> CHCl3(l) + 3HCl (g) CH4: 16.04 g/mol 3Cl2: 70.90 g/mol CHCl3: 119.4g/mol 3HCl: 36.46 g/mol a. What is the theoretical yield of CHCl3 in grams from 3.20g of CH4 b. What is the percent yield if 15.0 grams of CHCl3 are actually formed in this reaction

a. 23.9 g b. 62.8%

Fill in the needed reactant or product for each following reaction types and balance the equation a. Combination: Na + _____ --> 2NaCl b. Decomposition: NI3 --> ____ + ____ c. Single Replacement: Cl2 + KI --> ____ + ____ d. Double Replacement: KOH + HI ---> ___ + ___

a. 2Na + Cl₂ → 2NaCl b. 2NI₃ → N₂ + 3I₂ c. Cl₂ + 2KI → 2KCl + I₂ d. KOH + HI → KI + H₂O

What is the mass in grams of each quantity of lactic acid (C3H6O3 molar mass 90.08 g/mol), the compound responsible for the aching feeling of tired muscled during vigorous exercise? a. 3.60 mol b. 0.580 mol c. 7.3 x 10^24 molecules d. 6.56 x 10^22 molecules

a. 324g b. 52.2g c. 1.1 x 10³g d. 9.82g

Answer the following questions about the conversion of the sucrose (C12H22O11) in sugarcane to ethanol (C2H6O) and CO2 according to the following unbalanced equation. C12H22O11(s) + H2O(l) --> C2H6O(l) + CO2(g) a. What is the molar mass of sucrose b. Balance the given equation c. How many moles of ethanol are formed to form 2 mol of sucrose d. How many moles of water are needed to react with 10 moles of sucrose e. How many grams of ethanol are formed from 0.550 mol of sucrose f. How many grams of ethanol are formed from 34.2 g of sucrose g. What is the theoretical yield of ethanol in grams from 17.1 grams of sucrose h. If 1.25 g of ethanol are formed i the reaction in part (g), what is the percent yield.

a. 342.3 g/mol b. C₁₂H₂₂O₁₁ (s) + H₂O (l) → 4C₂H₆O(l) + 4 CO₂(g) c. 8mol d. 10mol e. 101g f. 18.4 g g. 9.21 g h. 13.6%

Calculate the formula weight and the molar mass of each compound a. NaNO2 (sodium nitrate) b. Al2(SO4)3 (aluminum sulfate) c. C6H8O6 (Vitamin C)

a. 69.00 amu, 69.00 g/mol b. 342.2 amu, 342.2 g/mol c. 176.12 amu, 176.12 g/mol

Classify each reaction as combustion, decomposition, single replacement, or double replacement a. 2Br-Cl --> Br2 + Cl2 b. F2 + 2 NaBr --> 2 NaF + Br2 c. 4Fe + 3O2 --> 2Fe2O3 d. HNO3 + KOH --> KNO3 + H2O

a. Decomposition b. Single replacement c. Combustion d. Double replacement

Identify the species that is oxidized and the species that is reduced in each reaction. Write out two half reactions to show how many electrons are gained or lost by each species. a. Fe + Cu^2+ --> Fe^2+ + Cu b. Cl2 + 2I^- --> I2 + 2Cl^- c. 2Na + Cl2 --> 2NaCl

a. Fe (oxidized), Cu⁺² (reduced) Fe → Fe⁺² + 2 e⁻ Cu²⁺ + 2e⁻ → Cu b. Cl₂ (reduced), 2I⁻ (oxidized) 2I⁻ → I₂ + 2e⁻ Cl₂ + 2e⁻ → 2Cl⁻ c. 2Na (oxidized), Cl₂ (reduced) 2Na → 2Na⁺ + 2e⁻ Cl₂ + 2e⁻ → 2Cl⁻

Balance each equation: a. Ni(s) + HCl(aq) --> NiCl2(aq) + H2(g) b. CH4 (g) + Cl2 (g) --> CCl4(g) + HCl (g) c. KCIO3 --> KCl + O2 d. Al2O3 + HCl --> AlCl3 + H2O e. Al(OH)3 + H2SO4 --> AL2(SO4)3 + H2O

a. Ni(s) + 2HCl (aq) →NiCl₂ (aq) + H₂(g) b. CH₄(g) + 4Cl₂(g) → CCl₄(g) + 4HCl c. 2KClO₃ → 2 KCl + 3O₂ d. Al₂O₃ + 6HCl → 2 AlCl₃ + 3H₂O e. 2Al(OH)₃ + 3 H₂(SO₄)₃ + 6H₂O

Using the balanced equation 2NO + O2 --> 2NO2, determine the limiting reactant under each of the following conditions a. 1.0 mol NO and 1.0 mol O2 b. 2.0 mol NO and 0.50 mol O2 c. 10.0 g NO and 10.0 g O2 d. 28.0 g NO and 16.0 g O2

a. No b. O2 c. NO d. NO

Label the reactants and products, and indicate how many atoms of each type of element are present on each side of the following equations a. 2 H2O2(aq) --> 2 H2O(l) + O2(g) b. 2 C8H18 + 25 O2 --> 16 CO2 + 18 H2O c. 2 Na3PO4(aq) + 3 MgCl2(aq) --> Mg3(PO4)2(s) + 6 NaCl(aq)

a. Reactant --> product 4H, 4O b. Reactant --> product 16C, 50O, 36H c. Reactant --> product 3Mg, 2P, 8O, 6Na, 6Cl