Q: Convert 0.00056 meters to scientific notation.

$$5.6 \times 10$$^{-4}$$\ \mathrm{m}$$

Q: A sample contains 3.00 moles of sodium atoms. How many atoms are present in the sample? (Use $$6.022 \times 10$$^{23}$$ atoms/mol)

$$1.81 \times 10$$^{24}$$ atoms

Q: A student needs to convert 5.0 kilometers to meters using dimensional analysis. Which setup is correct?

$$5.0\ \mathrm{km} \times \frac{1000\ \mathrm{m}}{1\ \mathrm{km}}$$

Question 1

Which of the following statements best describes the difference between a physical and a chemical property?

Accepted Answer

A physical property can be measured without changing the identity of the substance, while a chemical property involves a change in the substance's identity.

Question 2

A student measures the mass of a sample as 12.345 g and the volume as 4.1 mL. What is the density of the sample, reported with the correct number of significant figures?

Accepted Answer

$$\frac{12.345}{4.1} = 3.01\ \mathrm{g/mL}$$

Question 3

Which of the following is the correct symbol for the element potassium?

Accepted Answer

K

Question 4

A chemical reaction absorbs heat from its surroundings. Which term best describes this process?

Accepted Answer

Endothermic

Question 5

Convert 0.00056 meters to scientific notation.

Accepted Answer

$$5.6 	imes 10$$^{-4}$$\ \mathrm{m}$$

Question 6

Which of the following best describes the scientific method?

Accepted Answer

A systematic approach to research involving observation, hypothesis, experimentation, and conclusion.

Question 7

A sample contains 3.00 moles of sodium atoms. How many atoms are present in the sample? (Use $$6.022 	imes 10$$^{23}$$ atoms/mol)

Accepted Answer

$$1.81 	imes 10$$^{24}$$ atoms

Question 8

Which of the following is a diatomic element in its natural state?

Accepted Answer

Oxygen ($$\mathrm{O}_2)$$

Question 9

A compound is formed from magnesium and chlorine. What is the correct formula for this binary ionic compound?

Accepted Answer

$$\mathrm{MgCl}_2$$

Question 10

Which of the following temperature conversions is correct for converting $$25\ ^\circ\mathrm{C} to $$Kelvin?

Accepted Answer

$$25 + 273.15 = 298.15\ \mathrm{K}$$

Question 11

Which of the following is the correct charge for the sulfate ion?

Accepted Answer

$$-2$$

Question 12

A student needs to convert 5.0 kilometers to meters using dimensional analysis. Which setup is correct?

Accepted Answer

$$5.0\ \mathrm{km} 	imes \frac{1000\ \mathrm{m}}{1\ \mathrm{km}}$$

Question 13

Which of the following elements is a main group element?

Accepted Answer

Sodium ($$\mathrm{Na})$$

Question 14

How many significant figures are in the measurement 0.00450 g?

Accepted Answer

3

Question 15

Which of the following best describes an exothermic reaction?

Accepted Answer

A reaction that releases heat to its surroundings.

Question 16

Which of the following is the correct formula for calculating density?

Accepted Answer

$$\mathrm{Density} = \frac{\mathrm{mass}}{\mathrm{volume}}$$

Question 17

Which of the following ions has a charge of $$+1$$?

Accepted Answer

$$\mathrm{Na}^+$$

Question 18

Which of the following is NOT a correct statement about the periodic table?

Accepted Answer

Transition metals are found in Group 2.

Question 19

A student is asked to determine the number of significant figures in the result of $$2.50 	imes 3.1. $$What is the correct answer?

Accepted Answer

2

Question 20

Which of the following is the correct chemical symbol for the element with atomic number 8?

Accepted Answer

O

Exam 1 Study Guide: Introduction to Chemistry – Key Concepts and Expectations

Guida di studio - Domande di pratica

Study guide - Flashcard