Question 1

Which of the following statements best describes the difference between precision and accuracy in scientific measurements?

Accepted Answer

Precision refers to how close repeated measurements are to each other, while accuracy refers to how close a measurement is to the true value.

Question 2

A student measures the mass of a sample as 12.345 g and the volume as 6.7 mL. What is the density of the sample, reported with the correct number of significant figures?

Accepted Answer

$$1.8\ \mathrm{g/mL}$$

Question 3

Which of the following is an example of an intensive property?

Accepted Answer

Density

Question 4

Convert 5.00 km to meters using dimensional analysis. (1 km = 1000 m)

Accepted Answer

$$5000\ \mathrm{m}$$

Question 5

Which of the following elements is a metalloid?

Accepted Answer

Silicon

Question 6

A neutral atom of chlorine has 17 protons. How many electrons does it have?

Accepted Answer

17

Question 7

What is the charge of an ion with 12 protons and 10 electrons?

Accepted Answer

$$+2$$

Question 8

Which group on the periodic table contains elements that are all gases at room temperature and are chemically inert?

Accepted Answer

Noble gases

Question 9

What is the correct formula for magnesium chloride?

Accepted Answer

$$\mathrm{$$MgCl_2$$}$$

Question 10

Which of the following is the correct name for $$\mathrm{N_2O_4}$$?

Accepted Answer

Dinitrogen tetraoxide

Question 11

What is the average atomic mass of chlorine if $$75.78\% of $$chlorine atoms have a mass of $$34.969\ \mathrm{amu}$$ and $$24.22\%$$ have a mass of $$36.966\ \mathrm{amu}$$?

Accepted Answer

$$35.45\ \mathrm{amu}$$

Question 12

Which subatomic particle has a mass of approximately $$1\ \mathrm{amu}$$ and a charge of $$+1$$?

Accepted Answer

Proton

Question 13

A compound has the molecular formula $$\mathrm{C_6H_{12}O_6$}. $$What is its empirical formula?

Accepted Answer

$$\mathrm{CH_2O}$$

Question 14

Which of the following ions has the same number of electrons as a neutral neon atom?

Accepted Answer

$$\mathrm{Na^+}$$

Question 15

What is the correct formula for the ionic compound formed between aluminum and sulfate?

Accepted Answer

$$\mathrm{Al_2$(SO_4$)_3}$$

Question 16

Which of the following is the correct name for $$\mathrm{K_2SO_4}$$?

Accepted Answer

Potassium sulfate

Question 17

A sample contains $$80\%$$ $$^{35}\mathrm{Cl} ($$mass $$= 34.969\ \mathrm{amu}) $$and $$20\%$$ $$^{37}\mathrm{Cl} ($$mass $$= 36.966\ \mathrm{amu}). $$Calculate the average atomic mass.

Accepted Answer

$$35.37\ \mathrm{amu}$$

Question 18

Which of the following is a correct statement about isotopes?

Accepted Answer

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

Question 19

Which of the following formulas represents an ionic compound?

Accepted Answer

$$\mathrm{NaCl}$$

Question 20

If a compound is composed of $$40.0\%$$ carbon, $$6.7\%$$ hydrogen, and $$53.3\%$$ oxygen by mass, what is its empirical formula?

Accepted Answer

$$\mathrm{CH_2O}$$

General Chemistry Exam 1 Study Guide: Matter, Energy, Atoms, Molecules, and Ions

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