Chem 112 General Chemistry Exam 1 Fall 2023

Which of the following is a step that is NOT in the scientific method?

• making observations

• modifying laws

• formulating hypotheses

• performing experiments

Which of the following quantities is equivalent to 594 mg?

• 0.594 µg

• 0.594 g

• 5.94 g

• 0.00594 kg

• 594,000 kg

You have a 100 gram sample of each of the following metals. Which sample has the largest volume?

• Aluminum, d = 2.7 g/cm3

• Magnesium, d = 1.74 g/cm3

• Gold, d = 19.3 g/cm3

• Silven d = 10.5 g/cm3

• Iron, d = 7.86 g/cm3

You have a sample of each of the following five metals, with the mass and density of each sample given. Which sample has the smallest volume?

• Al, mass = 138 g, d = 2.7 g/cm3

• Mg, mass = 105 g, d = 1.74 g/cm3

• Cu, mass = 225 g, d = 8.92 g/cm3

• Ag, mass = 215 g, d = 10.5 g/cm3

• Fe, mass = 235 g, d = 7.86 g/cm3

A student is determining the density of an unknown metal with a mass of 32.56 g. The student partially fills a graduated cylinder with water and measures the volume of the water by itself as 14.78 mL. The student then adds the metal to the water and measures the new volume as 20.44 mL. What is the identity of the metal?

• Aluminum, d = 2.70 g/mL

• Tin, d = 5.75 g/mL

• Magnesium, d = 1.74 g/mL

• Lead, d = 11.3 g/mL

Which one of the following would have approximately the same mass as 40.0 cm3 of lead (d = 11.3 g/cm3)?

• 43.0 cm3 of silver (d = 10.5 g/cm3)

• 15.3 cm3 of gold (d = 19.3 g/cm3)

• 4.50 cm3 of copper (d = 8.98 g/cm3)

• 230 cm3 of tin (5.75 g/cm3)

How many significant figures does the number 48.050 have?

• 3

• 2

• 4

• 6

• 5

Which of the following numbers contains five significant figures?

• 50.260

• 1000.01

• 0.07246

• 2.02470

• 9935.10

The accepted value for the density of iron is 7.9 g/mL. Which of the following sets of experimental data for the density of iron is the most accurate?

• Group 1: 7.98 g/mL, 7.85 g/mL

• Group 2: 7.65 g/mL, 7.64 g/mL

• Group 3: 7.03 g/mL, 8.54 g/mL

• Group 4: 5.43 g/mL, 5.47 g/mL

• Group 5: 7.93 g/mL, 7.92 g/mL

A beaker of water has an initial mass of 455.2 g. After it has been left uncovered for several days, some of the water has evaporated. The new mass of the beaker is found to be 422.55 g using a more precise balance. Choose a value that expresses the mass of the evaporated water using the correct number of significant figures.

• 32.65 g

• 32.650 g

• 32.7 g

• 422.55 g

• 33 g