Question 1

Which of the following best describes a chemical change?

Accepted Answer

Iron rusting when exposed to air

Question 2

A medication is prescribed at a dose of 2.5 mg/kg. If a patient weighs 70 kg, how many milligrams of the medication should be administered? (Give your answer with the correct number of significant figures.)

Accepted Answer

$$1.75 	imes 10^2$ mg

Question 3

Which of the following statements about accuracy and precision is correct?

Accepted Answer

Accuracy refers to how close measurements are to the true value, while precision refers to how close measurements are to each other.

Question 4

Convert a temperature of $$98.6\ ^\circ\mathrm{F} ($$normal human body temperature) to degrees Celsius. Use the formula $$^\circ\mathrm{C} = ( ^\circ\mathrm{F} - 32 ) 	imes \frac{5}{9}.$$

Accepted Answer

$$37.0\ ^\circ\mathrm{C}$$

Question 5

Which of the following is the correct nuclear symbol for an isotope of carbon with 7 neutrons?

Accepted Answer

$$\mathrm{^{13}_{6}C}$$

Question 6

A sample of a radioactive isotope has a half-life of 4 hours. If you start with 80 mg, how much remains after 12 hours?

Accepted Answer

$$10 mg$$

Question 7

Which of the following best describes the octet rule?

Accepted Answer

Atoms gain, lose, or share electrons to achieve eight electrons in their outermost shell.

Question 8

Which of the following ions is formed when magnesium reacts to achieve a noble gas configuration?

Accepted Answer

$$\mathrm{Mg}^{2+}$$

Question 9

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

Accepted Answer

$$\mathrm{Al}_2(\mathrm{SO}_4)_3$$

Question 10

Which of the following is the correct Lewis structure for water ($$\mathrm{H}_2\mathrm{O}$$)?

Accepted Answer

Oxygen in the center with two single bonds to hydrogen and two lone pairs on oxygen.

Question 11

Which of the following is the correct name for $$\mathrm{N}_2\mathrm{O}_5$$?

Accepted Answer

Dinitrogen pentoxide

Question 12

Which of the following best describes the difference between ionic and covalent bonding?

Accepted Answer

Ionic bonding involves the transfer of electrons, while covalent bonding involves the sharing of electrons.

Question 13

A patient’s temperature is measured as $$39.0\ ^\circ\mathrm{C}. $$What is this temperature in Kelvin? (Use $$K = ^\circ\mathrm{C} + 273.15)$$

Accepted Answer

$$312.2\ \mathrm{K}$$

Question 14

Which of the following is a correct example of scientific notation for the number 0.00056?

Accepted Answer

$$5.6 	imes 10$$^{-4}$$

Question 15

Which of the following is the correct electron configuration for a neutral sodium atom ($$Z=11$$)?

Accepted Answer

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

Question 16

Which of the following is a polyatomic ion?

Accepted Answer

$$\mathrm{NO}_3^-$$

Question 17

Which type of radioactive decay results in the emission of a helium nucleus?

Accepted Answer

Alpha decay

Question 18

A solution contains $$0.250 L of $$saline. How many milliliters is this? (1 L = 1000 mL)

Accepted Answer

$$250 mL$$

Question 19

Which of the following best describes a physical change?

Accepted Answer

Sugar dissolving in water

Question 20

Which of the following is the correct name for $$\mathrm{FeCl}_3$$?

Accepted Answer

Iron(III) chloride

CHEM 130 Exam 1 Study Guide: Chemistry Basics, Atoms, and Compounds

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