Q: Express $$0.000000000074$$ meters in scientific notation.

$$7.4 \times 10$$^{-11}$$\ \mathrm{m}$$

Question 1

Which of the following is an example of a chemical change?

Accepted Answer

Iron rusting when exposed to oxygen

Question 2

A sample of a substance has a mass of 25.0 g and occupies a volume of 5.00 cm$$^3. $$What is its density, and which metal is it most likely to be if the possible densities are: aluminum (2.70 g/cm$$^3$$), zinc (7.14 g/cm$$^3$$), copper (8.94 g/cm$$^3$$), and lead (11.3 g/cm$$^3$$)?

Accepted Answer

$$5.00\ \mathrm{g/cm^3$}$$; most likely zinc

Question 3

Which of the following is an intensive property?

Accepted Answer

Density

Question 4

A student measures the length of a metal rod as 12.30 cm using a ruler with millimeter markings. How many significant figures are in this measurement?

Accepted Answer

4

Question 5

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture with uniform composition throughout, such as black coffee

Question 6

Convert 155 lbs to kilograms. (Use $$1\ \mathrm{kg} = 2.205\ \mathrm{lbs}.)$$

Accepted Answer

$$70.3\ \mathrm{kg}$$

Question 7

Which of the following statements about gases is correct?

Accepted Answer

Gases are compressible and expand to fill their container

Question 8

A cube of unknown metal has a side length of $$1.50\ \mathrm{cm}$$ and a mass of $$9.20\ \mathrm{g}. $$What is its density in $$\mathrm{g/cm^3$}$$? (Density = mass/volume)

Accepted Answer

$$2.73\ \mathrm{g/cm^3$}$$

Question 9

Which of the following is a compound?

Accepted Answer

Water ($$H_2O)$$

Question 10

A car travels 220 miles and gets 30 miles per gallon. How many gallons of gasoline are used?

Accepted Answer

$$7.33$$ gallons

Question 11

Which of the following is NOT a physical property?

Accepted Answer

Flammability

Question 12

Express $$0.000000000074$$ meters in scientific notation.

Accepted Answer

$$7.4 	imes 10$$^{-11}$$\ \mathrm{m}$$

Question 13

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

Accepted Answer

Orange juice with pulp

Question 14

A procedure requires $$20.0\ \mathrm{g} of $$ethanol. If the density of ethanol is $$0.789\ \mathrm{g/cm^3$}$$, what volume (in mL) should be delivered?

Accepted Answer

$$25.4\ \mathrm{mL}$$

Question 15

Which of the following is an exact number?

Accepted Answer

The number of students in a classroom

Question 16

Which of the following best describes a physical change?

Accepted Answer

Dissolving sugar in water

Question 17

How many significant figures are in the number $$0.004560$$?

Accepted Answer

4

Question 18

Which of the following is a derived SI unit?

Accepted Answer

Liter ($$L)$$

Question 19

A student adds $$1.028$$ and $$2.69. $$What is the correct answer with the proper number of decimal places?

Accepted Answer

$$3.72$$

Question 20

Which of the following is a correct conversion factor for dimensional analysis?

Accepted Answer

$$1\ \mathrm{ft} = 12\ \mathrm{in}$$

General Chemistry I: Introduction to Matter, Measurement, and Properties

Guida di studio - Domande di pratica

Study guide - Flashcard