Question 1

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture in which the composition is uniform throughout, such as salt dissolved in water.

Question 2

A sample of gold has a mass of $$19.3\ \mathrm{g}$$ and a volume of $$1.00\ \mathrm{cm}^3. $$What is the density of gold, and how many significant figures should the answer have?

Accepted Answer

$$19.3\ \mathrm{g/cm}^3$$ with 3 significant figures

Question 3

Which of the following changes is a chemical change?

Accepted Answer

Iron rusting when exposed to air

Question 4

A student measures the length of a metal rod as $$12.30\ \mathrm{cm}. $$How many significant figures are in this measurement?

Accepted Answer

4

Question 5

Which of the following statements about subatomic particles is correct?

Accepted Answer

Protons are positively charged and located in the nucleus.

Question 6

Given the isotope symbol $$^{37}_{17}\mathrm{Cl}^{-}$$, how many protons, neutrons, and electrons does this ion have?

Accepted Answer

17 protons, 20 neutrons, 18 electrons

Question 7

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

Accepted Answer

Density

Question 8

A sample of a substance has a melting point of $$0\ ^\circ\mathrm{C}$$ and a boiling point of $$100\ ^\circ\mathrm{C}. At$$ $$50\ ^\circ\mathrm{C}$$, what is its state of matter?

Accepted Answer

Liquid

Question 9

Which of the following best describes the trend in atomic radius across a period from left to right on the periodic table?

Accepted Answer

Atomic radius decreases due to increasing nuclear charge.

Question 10

Convert $$0.00560\ \mathrm{kg} to $$milligrams ($$\mathrm{mg}) $$using dimensional analysis. (1 kg = $$10^6 mg)$$

Accepted Answer

$$5,600\ \mathrm{mg}$$

Question 11

Which of the following electron configurations represents a neutral atom of magnesium ($$\mathrm{Mg}$$, atomic number 12)?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^6$$\ $$3s^2$$

Question 12

A student needs to convert $$25.0\ \mathrm{cm}^3 to $$liters ($$\mathrm{L}). $$Which of the following is the correct answer and number of significant figures? (1 L = $$1000\ \mathrm{cm}^3)$$

Accepted Answer

$$0.0250\ \mathrm{L}$$ with 3 significant figures

Question 13

Which of the following best describes a direct relationship between two variables on a graph?

Accepted Answer

As one variable increases, the other variable increases proportionally.

Question 14

Which of the following is the correct scientific notation for the number $$0.000347$$?

Accepted Answer

$$3.47 	imes 10$$^{-4}$$

Question 15

A neutral atom of calcium ($$\mathrm{Ca}) $$has an atomic number of 20 and a mass number of 40. How many neutrons does it have?

Accepted Answer

20

Question 16

Which of the following best explains why metals tend to have high electrical conductivity?

Accepted Answer

Metals have delocalized valence electrons that can move freely.

Question 17

A sample contains two isotopes of boron: $$^{10}\mathrm{B} (20$$% abundance, mass = 10.0 u) and $$^{11}\mathrm{B} (80$$% abundance, mass = 11.0 u). What is the average atomic mass of boron?

Accepted Answer

$$10.8\ \mathrm{u}$$

Question 18

Which of the following best describes the trend in ionization energy as you move down a group in the periodic table?

Accepted Answer

Ionization energy decreases because valence electrons are farther from the nucleus.

Question 19

A student is given a graph showing pressure and volume for a gas at constant temperature. The graph is a hyperbola. What type of relationship does this represent?

Accepted Answer

Inverse relationship

Question 20

Which of the following is the correct number of valence electrons for a neutral atom of phosphorus ($$\mathrm{P}$$, atomic number 15)?

Accepted Answer

5

Section 1 Study Guide: Introduction to Chemistry – Step-by-Step Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard