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Problem 88b
Write a ratio showing the relationship between the molar amounts of each element for each compound. (See Appendix IIA for color codes.) (b)
Problem 89a
Determine the number of moles of hydrogen atoms in each sample. a. 0.0885 mol C4H10 b. 1.3 mol CH4
Problem 89c
Determine the number of moles of hydrogen atoms in each sample. c. 2.4 mol C6H12
Problem 89d
Determine the number of moles of hydrogen atoms in each sample. d. 1.87 mol C8H18
Problem 90
Determine the number of moles of oxygen atoms in each sample. a. 4.88 mol H2O2 b. 2.15 mol N2O c. 0.0237 mol H2CO3 d. 24.1 mol CO2
Problem 91a
Calculate mass (in grams) of sodium in 8.5 g of each sodium containing food additive. a. NaCl (table salt) b. Na3PO4 (sodium phosphate) c. NaC7H5O2 (sodium benzoate) d. Na2C6H6O7 (sodium hydrogen citrate)
Problem 92a
Calculate the mass (in kilograms) of chlorine in 25 kg of each chlorofluorocarbon (CFC). a. CF2Cl2 c. C2F3Cl3 d. CF3Cl
Problem 92b
Calculate the mass (in kilograms) of chlorine in 25 kg of each chlorofluorocarbon (CFC). b. CFCl3
Problem 93
How many bromine atoms are present in 12.8 g of CH2Br2?
Problem 94
How many fluorine atoms are present in 45.3 g of C2F4?
Problem 96a
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound. a. 1.245 g Ni, 5.381 g I
Problem 96b
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound. b. 2.677 g Ba, 3.115 g Br
Problem 96c
A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound. c. 2.128 g Be, 7.557 g S, 15.107 g O
Problem 97a
Calculate the empirical formula for each stimulant based on its elemental mass percent composition.
a. nicotine (found in tobacco leaves): C 74.03%, H 8.70%, N 17.27%
b. caffeine (found in coffee beans): C 49.48%, H 5.19%, N 28.85%, O 16.48%
Problem 98a
Calculate the empirical formula for each natural flavor based on its elemental mass percent composition. a. methyl butyrate (component of apple taste and smell): C 58.80%, H 9.87%, O 31.33%
Problem 98b
Calculate the empirical formula for each natural flavor based on its elemental mass percent composition. b. vanillin (responsible for the taste and smell of vanilla): C 63.15%, H 5.30%, O 31.55%
Problem 99
The elemental mass percent composition of ibuprofen (a nonsteroidal anti-inflammatory drug [NSAID]) is 75.69% C, 8.80% H, and 15.51% O. Determine the empirical formula of ibuprofen.
Problem 100
The elemental mass percent composition of ascorbic acid (vitamin C) is 40.92% C, 4.58% H, and 54.50% O. Determine the empirical formula of ascorbic acid.
- What is the empirical formula of nitrogen chloride given that a 0.77 mg sample of nitrogen reacts with chlorine to form 6.61 mg of the chloride?
Problem 101
Problem 102
A 45.2-mg sample of phosphorus reacts with selenium to form 131.6 mg of the selenide. Determine the empirical formula of phosphorus selenide.
Problem 103
From the given empirical formula and molar mass, find the molecular formula of each compound. a. C6H7N, 186.24 g/mol
Problem 104a
From the given molar mass and empirical formula of several compounds, find the molecular formula of each compound. a. C4H9, 114.22 g/mol
Problem 104b
From the given molar mass and empirical formula of several compounds, find the molecular formula of each compound. b. CCl, 284.77 g/mol
Problem 104c
From the given molar mass and empirical formula of several compounds, find the molecular formula of each compound. c. C3H2N, 312.29 g/mol
Problem 105
Combustion analysis of a hydrocarbon produces 33.01 g CO2 and 13.51 g H2O. Calculate the empirical formula of the hydrocarbon.
Problem 106
Combustion analysis of naphthalene, a hydrocarbon used in mothballs, produces 8.80 g CO2 and 1.44 g H2O. Calculate the empirical formula of naphthalene.
Problem 107
The foul odor of rancid butter is due largely to butyric acid, a compound containing carbon, hydrogen, and oxygen. Combustion analysis of a 4.30-g sample of butyric acid produces 8.59 g CO2 and 3.52 g H2O. Determine the empirical formula of butyric acid.
Problem 108
Tartaric acid is the white, powdery substance that coats tart candies such as Sour Patch Kids. Combustion analysis of a 12.01-g sample of tartaric acid—which contains only carbon, hydrogen, and oxygen—produces 14.08 g CO2 and 4.32 g H2O. Determine the empirical formula of tartaric acid.
- Classify each compound as organic or inorganic: a. CaCO3 b. C4H8 c. C4H6O6 d. LiF
Problem 109
Problem 111
Classify each hydrocarbon as an alkane, alkene, or alkyne. a. H2C=CH−CH3 b. H3C−CH2−CH3 c. HC≡C−CH3 d. H3C−CH2−CH2−CH3