Question 1

Which of the following best describes why salt (NaCl) is classified as a compound and not a mixture?

Accepted Answer

Because it is made of two elements chemically bonded in a fixed ratio.

Question 2

A student observes that when sugar dissolves in water, the resulting solution is clear and uniform throughout. Which classification best describes this mixture?

Accepted Answer

Homogeneous mixture

Question 3

Which of the following is an example of a chemical change?

Accepted Answer

Rusting of iron

Question 4

A sample of gold has a mass of $$96.5\ \mathrm{g}$$ and a volume of $$5.00\ \mathrm{cm}^3. $$What is the density of gold in $$\mathrm{g/cm}^3$$?

Accepted Answer

$$19.3\ \mathrm{g/cm}^3$$

Question 5

Which of the following statements about the scientific method is correct?

Accepted Answer

A hypothesis is a tentative explanation that must be testable.

Question 6

Which of the following is an intensive property?

Accepted Answer

Density

Question 7

A thermometer reads $$25.0\ ^\circ\mathrm{C}. $$What is this temperature in Kelvin?

Accepted Answer

$$298.2\ \mathrm{K}$$

Question 8

Which separation technique would be most effective for separating a mixture of sand and salt water?

Accepted Answer

Filtration

Question 9

A student measures the mass of a sample three times and gets values of $$5.12\ \mathrm{g}$$, $$5.13\ \mathrm{g}$$, and $$5.11\ \mathrm{g}. $$The true mass is $$5.50\ \mathrm{g}. $$Which statement is correct?

Accepted Answer

The measurements are precise but not accurate.

Question 10

Which of the following best describes the difference between a crystalline solid and an amorphous solid?

Accepted Answer

Crystalline solids have a repeating, organized structure.

Question 11

A student records the following measurements: $$2.50\ \mathrm{cm}$$, $$2.5\ \mathrm{cm}$$, and $$2.500\ \mathrm{cm}. $$How many significant figures are in each measurement, respectively?

Accepted Answer

3, 2, 4

Question 12

Which of the following is a physical property of water?

Accepted Answer

It has a density of $$1.00\ \mathrm{g/cm}^3 at$$ $$4\ ^\circ\mathrm{C}.$$

Question 13

A sample of ethanol has a mass of $$46.0\ \mathrm{g}$$ and a volume of $$58.0\ \mathrm{mL}. $$Will it float or sink in water? (Density of water = $$1.00\ \mathrm{g/mL})$$

Accepted Answer

It will float because its density is less than water.

Question 14

Which of the following is an example of potential energy?

Accepted Answer

A stretched bowstring

Question 15

Convert $$5.00$$ inches to centimeters. ($$1\ \mathrm{in} = 2.54\ \mathrm{cm})$$

Accepted Answer

$$12.7\ \mathrm{cm}$$

Question 16

Which of the following best describes a systematic error?

Accepted Answer

Measurements are consistently too high or too low.

Question 17

A student adds $$12.11\ \mathrm{g}$$, $$18.0\ \mathrm{g}$$, and $$1.013\ \mathrm{g}. $$What is the sum with the correct number of decimal places?

Accepted Answer

$$31.1\ \mathrm{g}$$

Question 18

Which of the following is NOT a pure substance?

Accepted Answer

Salt water

Question 19

Which of the following best explains why the law of conservation of mass is considered a scientific law?

Accepted Answer

It describes what happens in chemical reactions, not why.

Question 20

A sample of gas occupies $$2.50\ \mathrm{L} at$$ $$25.0\ ^\circ\mathrm{C}. If $$the temperature increases to $$50.0\ ^\circ\mathrm{C} at $$constant pressure, what happens to the volume? (Assume ideal gas behavior.)

Accepted Answer

The volume increases.

Chapter 1: Matter, Measurement, and Problem Solving – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard