CHEM 1306 Study Guide: Step-by-Step Guidance for Key Concepts

Q1. The amount of space occupied by a substance is its ________.

Background

Topic: Basic Physical Properties

This question tests your understanding of fundamental physical properties of matter, specifically the terminology used to describe them.

Key Terms:

• Mass: The amount of matter in an object.

• Volume: The amount of space an object or substance occupies.

• Density: Mass per unit volume.

• Weight: The force of gravity on an object.

• Length: Measurement of distance.

Step-by-Step Guidance

1. Review the definitions of each term listed in the answer choices.

2. Identify which term specifically refers to the 'amount of space' something occupies.

3. Eliminate choices that refer to other properties (e.g., mass, weight, length, density).

Try solving on your own before revealing the answer!

Q2. Which of the following is a measurement of mass in the metric system?

Background

Topic: Metric System Units

This question tests your knowledge of metric units and their corresponding physical quantities.

Key Terms:

• Kilogram (kg): The base unit of mass in the metric system.

• Milliliter (mL): Unit of volume.

• Centimeter (cm): Unit of length.

• Degree Celsius (°C): Unit of temperature.

• Meter (m): Unit of length.

Step-by-Step Guidance

1. Recall the base units for mass, length, volume, and temperature in the metric system.

2. Match each answer choice to its corresponding physical quantity.

3. Identify which choice is the unit for mass.

Try solving on your own before revealing the answer!

Q3. A value of 36 mL is a measure of ________.

Background

Topic: Units and Physical Quantities

This question checks your ability to associate metric units with the correct physical property.

Key Terms:

• mL (milliliter): A unit of volume in the metric system.

Step-by-Step Guidance

1. Recall what physical quantity is measured in milliliters.

2. Review the definitions of the answer choices (density, mass, temperature, volume, length).

3. Match 'mL' to the correct property.

Try solving on your own before revealing the answer!

Q4. A value of 26.4 mcg is a measure of ________.

Background

Topic: Units and Physical Quantities

This question tests your understanding of metric prefixes and the physical quantities they measure.

Key Terms:

• mcg (microgram): A unit of mass equal to $1 \times 10^{-6}$ grams.

Step-by-Step Guidance

1. Recall what the prefix 'micro-' means in the metric system.

2. Identify which physical quantity is measured in micrograms.

3. Match 'mcg' to the correct property among the answer choices.

Try solving on your own before revealing the answer!

Q5. Which of the following measurements has two significant figures?

Background

Topic: Significant Figures

This question tests your ability to count significant figures in a measurement, which is important for reporting scientific data accurately.

Key Terms:

• Significant Figures: All the digits in a measurement that are known with certainty plus one estimated digit.

Step-by-Step Guidance

1. Review the rules for counting significant figures (e.g., leading zeros, captive zeros, trailing zeros with/without decimal points).

2. Apply these rules to each measurement given in the answer choices.

3. Identify which measurement contains exactly two significant figures.

Try solving on your own before revealing the answer!

Q6. Which of the following numbers contains the designated correct number of significant figures?

Background

Topic: Significant Figures

This question tests your ability to count and verify the number of significant figures in a given number.

Key Terms:

• Significant Figures: The digits in a number that contribute to its precision.

Step-by-Step Guidance

1. For each answer choice, count the number of significant figures in the number provided.

2. Compare your count to the number of significant figures stated in the answer choice.

3. Identify which answer choice is correct.

Try solving on your own before revealing the answer!

Q7. Which of the following examples illustrates a number that is correctly rounded to three significant figures?

Background

Topic: Rounding and Significant Figures

This question tests your ability to round numbers to a specified number of significant figures.

Key Terms:

• Rounding: Adjusting a number to a specified number of significant digits.

Step-by-Step Guidance

1. Review how to round a number to three significant figures.

2. For each example, check if the rounded value has exactly three significant figures.

3. Identify which example is correct.

Try solving on your own before revealing the answer!

Q8. When 2610 + 11.7 + 0.22 are added, the answer to the correct number of decimal places is ________.

Background

Topic: Significant Figures in Addition

This question tests your understanding of how to report the correct number of decimal places when adding numbers.

Key Terms and Rules:

• When adding or subtracting, the result should have the same number of decimal places as the measurement with the fewest decimal places.

Step-by-Step Guidance

1. Write each number with its decimal places: 2610 (0 decimal places), 11.7 (1 decimal place), 0.22 (2 decimal places).

2. Add the numbers together.

3. Round the result to match the number with the fewest decimal places (in this case, 2610).

Try solving on your own before revealing the answer!

Q9. What is the relationship between grams and micrograms?

Background

Topic: Metric Prefixes and Unit Conversions

This question tests your knowledge of metric prefixes and how to convert between units.

Key Terms and Formulas:

• Micro- (μ): Prefix meaning $1 \times 10^{-6}$.

• 1 gram (g) = 1,000,000 micrograms (μg)

Step-by-Step Guidance

1. Recall the meaning of the prefix 'micro-'.

2. Set up the conversion factor between grams and micrograms.

3. Express the relationship as an equation: $1 \text{ g} = 1 \times 10^{6} \text{ μg}$.

Try solving on your own before revealing the answer!

Q10. Which one of the following substances will float in gasoline, which has a density of 0.74 g/mL? The density of each substance is shown in parentheses.

Background

Topic: Density and Buoyancy

This question tests your understanding of how density determines whether a substance will float or sink in another liquid.

Key Terms:

• Density: $\text{Density} = \frac{\text{mass}}{\text{volume}}$

• A substance will float if its density is less than the density of the liquid.

Step-by-Step Guidance

1. Compare the density of each substance to the density of gasoline (0.74 g/mL).

2. Identify which substance(s) have a density less than 0.74 g/mL.

3. The substance with a lower density will float.

Try solving on your own before revealing the answer!

Q11. What is the mass of 2.00 L of an intravenous glucose solution with a density of 1.15 g/mL?

Background

Topic: Density Calculations

This question tests your ability to use density as a conversion factor to find mass from volume.

Key Formula:

$\text{Density} = \frac{\text{mass}}{\text{volume}}$

Rearranged: $\text{mass} = \text{density} \times \text{volume}$

Step-by-Step Guidance

1. Convert the volume from liters to milliliters: $1 \text{ L} = 1000 \text{ mL}$.

2. Multiply the volume in mL by the density (in g/mL) to find the mass in grams.

3. If needed, convert the mass from grams to kilograms ($1 \text{ kg} = 1000 \text{ g}$).

Try solving on your own before revealing the answer!

Q12. What is the mass of 53 mL of ethanol, which has a density of 0.79 g/mL?

Background

Topic: Density Calculations

This question tests your ability to calculate mass from volume and density.

Key Formula:

$\text{mass} = \text{density} \times \text{volume}$

Step-by-Step Guidance

1. Write down the given values: volume = 53 mL, density = 0.79 g/mL.

2. Multiply the volume by the density to find the mass in grams.

3. Check if the answer needs to be rounded to the correct number of significant figures.

Try solving on your own before revealing the answer!

Q13. The density of a solution is 1.18 g/mL. Its specific gravity is ________.

Background

Topic: Density and Specific Gravity

This question tests your understanding of the relationship between density and specific gravity.

Key Terms and Formula:

• Specific Gravity: The ratio of the density of a substance to the density of water (at 4°C, water's density is 1.00 g/mL).

• $\text{Specific Gravity} = \frac{\text{Density of substance}}{\text{Density of water}}$

Step-by-Step Guidance

1. Write the density of the solution (1.18 g/mL) and the density of water (1.00 g/mL).

2. Set up the formula for specific gravity.

3. Divide the density of the solution by the density of water.

Try solving on your own before revealing the answer!

Q14. A piece of iron with a mass of 119 g is placed in a graduated cylinder, where the water level is 57 mL. The water level rises to 72 mL. What is the density of the iron?

Background

Topic: Density Calculation Using Water Displacement

This question tests your ability to determine the density of an object using mass and volume (found by water displacement).

Key Formula:

$\text{Density} = \frac{\text{mass}}{\text{volume}}$

Step-by-Step Guidance

1. Calculate the volume of the iron by subtracting the initial water level from the final water level: $\text{Volume} = 72 \text{ mL} - 57 \text{ mL}$.

2. Write down the mass of the iron (119 g).

3. Plug the mass and calculated volume into the density formula.

Try solving on your own before revealing the answer!