Question 1

Which of the following best illustrates the Law of Definite Proportions?

Accepted Answer

A 10 g sample of NaCl contains the same mass ratio of sodium to chlorine as a 100 g sample of NaCl.

Question 2

Which of the following is the correct scientific notation for the number 0.000456?

Accepted Answer

$$4.56 	imes 10$$^{-4}$$

Question 3

A student measures the mass of a sample three times and gets values of 2.51 g, 2.50 g, and 2.52 g. The true mass is 2.80 g. Which statement best describes the data?

Accepted Answer

The data are precise but not accurate.

Question 4

Which of the following is a chemical change?

Accepted Answer

Burning magnesium ribbon in air to form magnesium oxide.

Question 5

Which of the following is a heterogeneous mixture?

Accepted Answer

Salad with lettuce, tomatoes, and cucumbers

Question 6

How many significant figures are in the measurement 0.0045600 g?

Accepted Answer

6

Question 7

Which of the following correctly converts 25.0 °C to Kelvin?

Accepted Answer

$$25.0 + 273.15 = 298.15\ \mathrm{K}$$

Question 8

Which of the following is the correct formula for ammonium sulfate?

Accepted Answer

$$\mathrm{(NH_4$)_2SO_4}$$

Question 9

A sample contains $$3.01 	imes 10$$^{23}$$ molecules of CO_2$. How many moles of CO_2$ are present?

Accepted Answer

$$0.500$$ mol

Question 10

Which of the following elements is a metalloid?

Accepted Answer

Boron (B)

Question 11

Which of the following is the correct name for $$\mathrm{$$FeCl_3$$}$$?

Accepted Answer

Iron(III) chloride

Question 12

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes of an element have the same number of protons but different numbers of neutrons.

Question 13

A compound contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is its empirical formula?

Accepted Answer

$$\mathrm{CH_2O}$$

Question 14

Which of the following is a physical property?

Accepted Answer

Density

Question 15

Which of the following is the correct formula for the nitrate ion?

Accepted Answer

$$\mathrm{NO_3$^-}$$

Question 16

A student needs to convert 5.00 inches to centimeters. Which conversion factor should be used?

Accepted Answer

$$1\ \mathrm{in} = 2.54\ \mathrm{cm}$$

Question 17

Which of the following best describes the difference between a compound and a mixture?

Accepted Answer

A compound is made of two or more elements chemically combined, while a mixture is a physical blend of substances.

Question 18

Which of the following is the correct symbol for an ion with 17 protons and 18 electrons?

Accepted Answer

$$\mathrm{Cl^-}$$

Question 19

Which of the following is the correct order of prefixes from largest to smallest?

Accepted Answer

mega, kilo, centi, milli, nano

Question 20

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?

Accepted Answer

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

General Chemistry I: Exam 1 Study Guide – Fundamental Concepts and Skills

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드