Q: Convert 0.0250 km to centimeters using dimensional analysis.

$$2.50 \times 10^4$\ \mathrm{cm}$$

Q: If the pH of a solution is 3.00, what is the hydrogen ion concentration $$[\mathrm{H^+}]$$?

$$[\mathrm{H^+}] = 1.0 \times 10$$^{-3}$$\ \mathrm{M}$$

Question 1

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

Accepted Answer

Mass

Question 2

A student mixes sand and salt in a beaker. Which separation technique would best separate these two substances?

Accepted Answer

Filtration

Question 3

Which of the following pairs of elements will most likely form an ionic compound?

Accepted Answer

Sodium and Chlorine

Question 4

A student measures the mass of a sample as 12.345 g. If the balance is accurate to 0.001 g, how many significant figures should be reported?

Accepted Answer

5

Question 5

Which statement best describes the difference between accuracy and precision?

Accepted Answer

Accuracy is how close measurements are to the true value; precision is how close measurements are to each other.

Question 6

Which state of matter has a definite volume but no definite shape?

Accepted Answer

Liquid

Question 7

A block of metal has a mass of 45.0 g and a volume of 15.0 cm$$^3. $$What is its density?

Accepted Answer

$$3.0\ \mathrm{g/cm^3$}$$

Question 8

Which of the following elements is a metalloid?

Accepted Answer

Silicon

Question 9

Convert 0.0250 km to centimeters using dimensional analysis.

Accepted Answer

$$2.50 	imes 10^4$\ \mathrm{cm}$$

Question 10

A compound contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is the empirical formula?

Accepted Answer

$$\mathrm{CH_2O}$$

Question 11

Which of the following is the solute in a solution of salt water?

Accepted Answer

Salt

Question 12

Which solution is most likely to be unsaturated?

Accepted Answer

A solution in which more solute can dissolve

Question 13

According to Beer's Law, which equation correctly relates absorbance ($$A$$), molar absorptivity ($$\varepsilon$$), path length ($$l$$), and concentration ($$c$$)?

Accepted Answer

$$A = \varepsilon l c$$

Question 14

How many moles of oxygen atoms are present in 1.00 mole of $$\mathrm{H_2SO_4}$$?

Accepted Answer

4.00 moles

Question 15

If the pH of a solution is 3.00, what is the hydrogen ion concentration $$[\mathrm{H^+}]$$?

Accepted Answer

$$[\mathrm{H^+}] = 1.0 	imes 10$$^{-3}$$\ \mathrm{M}$$

Question 16

Which equation correctly relates the energy ($$E) of a $$photon to its frequency ($$
u$$)?

Accepted Answer

$$E = h 
u$$

Question 17

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

Accepted Answer

Alpha decay

Question 18

How many protons, neutrons, and electrons are in $$^{14}\mathrm{C} ($$carbon-14)?

Accepted Answer

6 protons, 8 neutrons, 6 electrons

Question 19

Which scientist is credited with discovering the electron?

Accepted Answer

Thomson

Question 20

What is the electron configuration for a neutral oxygen atom?

Accepted Answer

$$1s^2$$\ $$2s^2$$\ $$2p^4$$

General Chemistry Study Guide: Core Concepts and Skills (Units 1–3)

Guida di studio - Domande di pratica

Study guide - Flashcard