Title: Chapter 3: Composition of Substances and Solutions
Course: Test

Q: Which of the following compounds contains the largest number of atoms?
- 1.00 mole of NH_3
- 1.00 mole of H_2SO_4
- 1.00 mole of HBr
A: 1.00 mole of H_2SO_4

Q: What is the molar mass of (NH_4)_3PO_4?
- 113 g
- 121 g
- 149 g
A: 149 g

Q: What is the mass in grams of 6.022 × 10^23 molecules of CO_2?
- 22 g
- 44 g
- 66 g
A: 44 g

Q: What is the total number of atoms contained in 2.00 moles of iron?
- 118
- 6.02 ×10^23
- 1.2 ×10^24
A: 1.2 ×10^24

Q: What is the molar mass of K_2CO_3?
- 138 g/mol
- 106 g/mol
- 99 g/mol
A: 138 g/mol

Q: What is the total number of atoms contained in 1.00 mole of sodium?
- 118
- 6.02 × 10^23
- 1.2 × 10^24
A: 6.02 × 10^23

Q: If a hazardous bottle is labeled 20.2 percent by mass Hydrochloric Acid, HCl, with a density of 1.096 g/mL, calculate the molarity of the HCl solution.
- 6.07 M
- 0.22 M
- 14.7 M
A: 6.07 M

Q: To dilute a HCl solution from 0.500 M to 0.100 M the final volume must be:
- 1/5 the original volume
- 5 times the original volume
- 50 L
A: 5 times the original volume

Q: How would you prepare a 1 M solution of sodium hydroxide?
- add 40.0 grams of sodium hydroxide to 1 L of water
- add 40.0 grams of sodium hydroxide to 100 L of water
- add 40.0 grams of sodium hydroxide to 10 L of water
A: add 40.0 grams of sodium hydroxide to 1 L of water

Q: How would you prepare a 0.5 M solution of sodium hydroxide?
- add 40.0 grams of sodium hydroxide to 1 L of water
- add 20.0 grams of sodium hydroxide to 1 L of water
- add 20.0 grams of sodium hydroxide to 10 L of water
A: add 20.0 grams of sodium hydroxide to 1 L of water

Q: An experiment requires 15.0 mL of a 0.100 M solution of HCl. If you have a 12.0 M HCl stock solution in the laboratory, how would you prepare enough 0.1 M solution to run at least 3 experiments?
- add 0.833 mL 12 M HCl stock solution to 99.167 mL water
- add 0.833 mL 12 M HCl stock solution to 49.167 mL water
- add 0.833 mL 12 M HCl stock solution to 199.167 mL water
A: add 0.833 mL 12 M HCl stock solution to 99.167 mL water

Q: What is the mass in grams of 1.59 moles of aluminum oxide?
- 162 g
- 0.0156 g
- 64.1 g
A: 162 g

Q: What is the mass in grams of 0.852 moles of ferric oxide?
- 5.34 × 10^-3 g
- 187 g
- 136 g
A: 136 g

Q: How many moles are in 1.77 kg of cuprous sulfate?
- 7.93 × 10^-3 moles
- 7.93 moles
- 395 moles
A: 7.93 moles

Q: How many grams are in 2.05 × 10^23 molecules of dinitrogen pentoxide?
- 317 g
- 36.8 g
- 0.00315 g
A: 36.8 g

Q: How many grams are in 1.02 × 10^22 molecules of nitric acid?
- 1.07 g
- 3720 g
- 2.69 × 10^-4 g
A: 1.07 g

Q: What is the total number of atoms contained in 2.11 moles of nickel?
- 2.85 × 10^23 atoms
- 1.27 × 10^24 atoms
- 3.50 × 10^-24 atoms
A: 1.27 × 10^24 atoms

Q: How many atoms are in 1.00 mole of Au?
- 6.02 × 10^23 atoms
- 1.66 × 10^-24 atoms
- 197 atoms
A: 6.02 × 10^23 atoms

Q: A 44.8 g rhodium sample contains how many rhodium atoms?
- 2.62 × 10^23 atoms
- 6.02 × 10^23 atoms
- 2.70 × 10^25 atoms
A: 2.62 × 10^23 atoms

Q: What is the molar mass of potassium nitrate?
- 85.10 g/mol
- 140.20 g/mol
- 101.10 g/mol
A: 101.10 g/mol

Q: Commercial grade fuming nitric acid contains about 90% HNO_3 by mass with a density of 1.50 g/mL, calculate the molarity of the HNO_3 solution.
- 0.214 M
- 21.4 M
- 2.14 M
A: 21.4 M

Q: Which of the following is a method used to allow scientists to determine an empirical formula and identify an organic compound by combusting a sample and the resulting combustion products are quantitatively analyzed?
- gravimetric analysis
- combustion analysis
- thermal analysis
A: combustion analysis

Q: A 3.00 g sample of unknown hydrocarbon is prepared for combustion analysis. After the hydrocarbon undergoes complete combustion, 8.80 g of CO_2 and 5.40 g of H_2O are produced. What is the empirical formula of the unknown?
- CH_3
- CH
- CH_2
A: CH_3

Q: A 0.125 g sample of unknown hydrocarbon is prepared for combustion analysis. After the hydrocarbon undergoes complete combustion, 0.4225 g of CO_2 and 0.0865 g of H_2O are produced. What is the empirical formula of the unknown?
- CH_3
- CH
- CH_2
A: CH

Q: An unknown organic compound (0.315 g) containing only C, H, and O produces 0.771 of CO_2 and 0.105 g of H_2O when it undergoes complete combustion. The approximate molar mass is 108 g/mol. Which of the following compounds could be the identification of the unknown?
- para-Cresol, CH_3C_6H_4(OH)
- Benzyl alcohol, C_6H_5CH_2OH
- 1,2-Benzoquinone, C_6H_4O_2
A: 1,2-Benzoquinone, C_6H_4O_2

Q: Which of the following is an experimental technique used to determine the mass percent of elements found in a compound?
- gravimetric analysis
- mass analysis
- elemental analysis
A: elemental analysis

Q: An unknown hydrocarbon compound was analyzed for hydrogen by elemental analysis and results show that it contains 15.88 % H. What is the empirical formula?
- C_4H_9
- C_8H_18
- C_12H_27
A: C_4H_9

Q: A 5.91 g unknown sample analyzed by elemental analysis revealed a composition of 37.51 % C. In addition, it was determined that the sample contains 1.4830 × 10^23 hydrogen atoms and 1.2966 × 10^23 oxygen atoms. What is the empirical formula?
- C_6H_8O_7
- C_5H_6O_3
- C_8H_16O_5
A: C_6H_8O_7

Q: What is the concentration in ppm of a 3.7 L solution (d = 1.00 g/mL) containing 4.21 × 10^-7 kg of the pesticide DDT?
- 1.14 × 10^-1 ppm
- 1.14 × 10^2 ppm
- 1.14 × 10^1 ppm
A: 1.14 × 10^-1 ppm

Q: When a salt is dissolved in water, it is represented by the following notation in a chemical reaction?
- (aq)
- (l)
- (s)
A: (aq)

Q: How is a solid phase represented in a chemical reaction?
- (s)
- (g)
- (l)
A: (s)

Q: How is a liquid phase represented in a chemical reaction?
- (s)
- (g)
- (l)
A: (l)

Q: How is a gas phase represented in a chemical reaction?
- (s)
- (g)
- (l)
A: (g)

Q: What are the proper units for molar mass in chemistry?
- amu
- g/mol
- g/mmol
A: g/mol

Q: How many atoms can be found in a mole of mercury?
- 201 atoms
- 6.02 × 10^23 atoms
- 1.21 × 10^26 atoms
A: 6.02 × 10^23 atoms

Q: A 21.8 g sample of water contains how many water molecules?
- 7.29 × 10^23 molecules
- 6.02 × 10^23 molecules
- 2.01 × 10^-24 molecules
A: 7.29 × 10^23 molecules

Q: A sample has a molar mass of 143 g/mol, identify the sample.
- AuCl
- AcCl
- AgCl
A: AgCl

Q: What is the molar mass of 2.50 g of an unknown sample dissolved in 130. mL of water with a concentration of 0.480 M?
- 0.062 g/mol
- 8.65 g/mol
- 40.1 g/mol
A: 40.1 g/mol

Q: 2.50 g of an unknown base is dissolved in 289 mL of water and has a concentration of 0.216 M. What is the identification of the unknown base?
- NaOH
- LiOH
- KOH
A: NaOH

Q: How many grams of Hydrogen are present in three moles of Hydrogen?
- two grams
- six grams
- one gram
A: six grams

Q: Which of the following compounds contains the largest number of atoms?
- 1.00 mole of NH_3
- 1.00 mole of H_2SO_4
- 1.00 mole of HBr
A: 1.00 mole of H_2SO_4

Q: How many atoms are in 12.8 g of copper metal?
- 7.71 × 10^24 atoms
- 1.21 × 10^23 atoms
- 3.34 × 10^-25 atoms
A: 1.21 × 10^23 atoms

Q: How many grams contain 1.45 × 10^21 zinc atoms?
- 1.57 × 10^-1 g
- 5.71 × 10^46 g
- 2.41 × 10^-3 g
A: 1.57 × 10^-1 g

Q: How many moles are in 11.0 g of silver metal?
- 9.81 moles
- 1.19 × 10^3 moles
- 1.02 × 10^-1 moles
A: 1.02 × 10^-1 moles

Q: What is Avogadro’s number?
- 6.022 × 10^23 particles/mole
- 6.022 × 10^22 particles/mole
- 6.022 × 10^24 particles/mole
A: 6.022 × 10^23 particles/mole

Q: Which of the following 85.0 g samples contain the greatest number of atoms?
- zinc
- gold
- zirconium
A: zinc

Q: Which of the following 49.5 g samples contain the fewest number of atoms?
- lead
- platinum
- iron
A: lead

Q: How many atoms are in 1 mole of calcium?
- 6.022 × 10^23 atoms
- 6.022 × 10^-23 atoms
- 6.022 × 10^22 atoms
A: 6.022 × 10^23 atoms

Q: How many moles contain 6.022 × 10^23 lithium atoms?
- 6.022 × 10^23 moles
- 1 mole
- 2 moles
A: 1 mole