Question 1

Which of the following statements best describes a chemical change?

Accepted Answer

A piece of iron rusts when left outside in the rain.

Question 2

A sample of a compound contains only sodium and chlorine. Which of the following best classifies this sample?

Accepted Answer

A pure substance, specifically a compound.

Question 3

Which of the following is the correct number of significant figures in the measurement $$0.00450 g$$?

Accepted Answer

3

Question 4

Convert $$2.75$$ kilometers to centimeters. ($$1 km$$ $$= 1000 m$$, $$1 m$$ $$= 100 cm)$$

Accepted Answer

$$2.75 	imes 10^5$ cm

Question 5

A patient receives $$500 mL of a $$saline solution. If the density of the solution is $$1.05 g/mL$$, what is the mass of the solution in grams?

Accepted Answer

$$525 g$$

Question 6

Which of the following best describes the arrangement of particles in a solid?

Accepted Answer

Particles are closely packed in a fixed, orderly arrangement.

Question 7

A nutrition label states that a snack contains $$10 g of $$fat, $$5 g of $$protein, and $$20 g of $$carbohydrates. What is the total energy content in calories (cal)? (Fat: $$9$$ cal/g, Protein: $$4$$ cal/g, Carbohydrate: $$4$$ cal/g)

Accepted Answer

$$170$$ cal

Question 8

Which of the following is the correct symbol for an isotope of carbon with $$6$$ protons and $$8$$ neutrons?

Accepted Answer

$$^{14}\mathrm{C}$$

Question 9

An atom of magnesium has an atomic number of $$12$$ and a mass number of $$25. $$How many neutrons does it have?

Accepted Answer

$$13$$

Question 10

Which of the following elements is a noble gas?

Accepted Answer

Neon

Question 11

Which of the following ions has $$10$$ electrons?

Accepted Answer

$$\mathrm{Na}^+$$

Question 12

Which of the following best describes a cation?

Accepted Answer

An atom that has lost one or more electrons and has a positive charge.

Question 13

Which group on the periodic table contains the halogens?

Accepted Answer

Group 17

Question 14

What is the formula for the ionic compound formed between magnesium and chlorine?

Accepted Answer

$$\mathrm{MgCl}_2$$

Question 15

Which of the following is a property of covalent compounds?

Accepted Answer

They generally have low melting points.

Question 16

How many valence electrons does an atom of sulfur (Group 16) have?

Accepted Answer

6

Question 17

Which of the following best describes an electrolyte?

Accepted Answer

A substance that conducts electricity when dissolved in water.

Question 18

A sample contains $$2.0 g of a $$substance with a volume of $$0.50 mL. $$What is its density in $$\mathrm{g/mL}$$?

Accepted Answer

$$4.0$$ $$\mathrm{g/mL}$$

Question 19

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

Accepted Answer

Dinitrogen pentoxide

Question 20

A student adds $$2.00 g of $$sodium chloride to $$100.0 g of $$water. What is the percent by mass of sodium chloride in the solution?

Accepted Answer

$$1.96\%$$

General Chemistry Exam 1 Study Guide: Key Concepts and Skills

Guida di studio - Domande di pratica

Study guide - Flashcard