Q: Convert 2.50 km to meters using dimensional analysis.

$$2.50 \times 10^3$\ \mathrm{m}$$

Question 1

Which of the following best describes why chemistry is considered the 'central science'?

Accepted Answer

Because it connects and explains phenomena in biology, physics, medicine, and engineering by understanding matter at the atomic and molecular level.

Question 2

Which of the following is an example of a homogeneous mixture?

Accepted Answer

Salt dissolved in water

Question 3

Which of the following changes is a chemical change?

Accepted Answer

Burning wood in a campfire

Question 4

A sample of gold has a mass of 96.5 g and a volume of 5.00 cm$$^3. $$What is the density of gold in g/cm$$^3$$?

Accepted Answer

$$19.3\ \mathrm{g/cm^3$}$$

Question 5

Which of the following statements best describes the Law of Conservation of Mass?

Accepted Answer

Mass is neither created nor destroyed during a chemical reaction.

Question 6

A scientist measures the mass of a sample three times and gets values of 8.12 g, 8.13 g, and 8.11 g. The true mass is 8.50 g. Which statement is correct?

Accepted Answer

The measurements are precise but not accurate.

Question 7

Convert 2.50 km to meters using dimensional analysis.

Accepted Answer

$$2.50 	imes 10^3$\ \mathrm{m}$$

Question 8

Which of the following is a derived SI unit?

Accepted Answer

Cubic meter (m$$^3)$$

Question 9

How many significant figures are in the measurement 0.0045600?

Accepted Answer

6

Question 10

Which of the following best describes a compound?

Accepted Answer

A pure substance composed of two or more elements in fixed, definite proportions.

Question 11

A car travels at a speed of 90.0 km/h. What is this speed in m/s? (1 km = 1000 m, 1 h = 3600 s)

Accepted Answer

$$25.0\ \mathrm{m/s}$$

Question 12

Which of the following is an example of a physical property?

Accepted Answer

Boiling point

Question 13

Which of the following is NOT a correct rule for counting significant figures?

Accepted Answer

Leading zeros are significant.

Question 14

A 1.00 L sample of seawater contains 35.0 g of salt. What is the concentration of salt in g/mL?

Accepted Answer

$$0.0350\ \mathrm{g/mL}$$

Question 15

Which of the following best describes potential energy?

Accepted Answer

Energy due to the position or composition of matter

Question 16

Which of the following is a heterogeneous mixture?

Accepted Answer

Oil and water

Question 17

A scientist reports a temperature increase as $$1.55 \pm 0.01\ ^\circ\mathrm{C}. $$What does this mean?

Accepted Answer

The temperature increase could be as high as $$1.56\ ^\circ\mathrm{C} or as $$low as $$1.54\ ^\circ\mathrm{C}.$$

Question 18

Which of the following is an intensive property?

Accepted Answer

Density

Question 19

Which of the following is the correct result (with proper significant figures) for $$4.56 	imes 1.4$$?

Accepted Answer

$$6.4$$

Question 20

Which of the following best describes a physical change?

Accepted Answer

Water boiling to form steam

Introduction to General Chemistry I: Matter, Measurement, and Basic Concepts

Guida di studio - Domande di pratica

Study guide - Flashcard