Question 1

Which of the following best describes a scientific theory?

Accepted Answer

A well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.

Question 2

A student observes ice melting in a beaker. Which of the following best describes this process?

Accepted Answer

A physical transformation because the composition of the substance does not change.

Question 3

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

Accepted Answer

Mass

Question 4

A sample of seawater is analyzed in a laboratory. How should it be classified?

Accepted Answer

Homogeneous mixture

Question 5

A student measures the length of a metal rod three times and records 12.1 cm, 12.2 cm, and 12.1 cm. The actual length is 13.0 cm. Which statement best describes the measurements?

Accepted Answer

The measurements are precise but not accurate.

Question 6

How many significant figures are in the measurement 0.004560 g?

Accepted Answer

5

Question 7

A student adds 12.11 g, 0.034 g, and 1.2 g. What is the sum, reported to the correct number of significant figures?

Accepted Answer

$$13.3\ \mathrm{g}$$

Question 8

Convert $$5.00\ \mathrm{km} to $$meters using the correct number of significant figures.

Accepted Answer

$$5000\ \mathrm{m}$$

Question 9

Which Greek prefix corresponds to $$1 	imes 10$$^{-9}$$?

Accepted Answer

nano-

Question 10

A sample of ethanol has a mass of $$46.0\ \mathrm{g}$$ and a volume of $$58.0\ \mathrm{mL}. $$What is its density?

Accepted Answer

$$0.793\ \mathrm{g/mL}$$

Question 11

Which scientist is credited with discovering the electron?

Accepted Answer

Thomson

Question 12

An isotope of carbon has 6 protons, 6 electrons, and 8 neutrons. What is its mass number?

Accepted Answer

$$14$$

Question 13

Given the following isotopes of magnesium: $$^{24}\mathrm{Mg} (78.99$$%, mass = 23.985 amu), $$^{25}\mathrm{Mg} (10.00$$%, mass = 24.986 amu), and $$^{26}\mathrm{Mg} (11.01$$%, mass = 25.983 amu), what is the average atomic mass of magnesium?

Accepted Answer

$$24.31\ \mathrm{amu}$$

Question 14

Which of the following best describes a noble gas?

Accepted Answer

A nonreactive element found in Group 18.

Question 15

Which of the following statements about Mendeleev's periodic table is correct?

Accepted Answer

He arranged elements by increasing atomic mass and predicted the existence of undiscovered elements.

Question 16

A patient’s body temperature is measured as $$102.2\ ^\circ\mathrm{F}. $$What is this temperature in Celsius? (Use $$C = \frac{5}{9}(F - 32))$$

Accepted Answer

$$39.0\ ^\circ\mathrm{C}$$

Question 17

Which of the following is a chemical change?

Accepted Answer

Rusting of iron

Question 18

A block of metal has a density of $$8.96\ \mathrm{g/cm^3$}$$ and a mass of $$134.4\ \mathrm{g}. $$What is its volume?

Accepted Answer

$$15.0\ \mathrm{cm^3$}$$

Question 19

Which of the following is a heterogeneous mixture?

Accepted Answer

Salad with lettuce, tomatoes, and cucumbers

Question 20

Which group on the periodic table contains the alkali metals?

Accepted Answer

Group 1

Introduction to Chemistry: Exam 1 Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard