Answer Key Chapter 1 – Chemistry: Atoms First 2e | OpenStax

Place a glass of water outside. It will freeze if the temperature is below 0 °C.

(a) law (states a consistently observed phenomenon, can be used for prediction); (b) theory (a widely accepted explanation of the behavior of matter); (c) hypothesis (a tentative explanation, can be investigated by experimentation)

(a) symbolic, microscopic; (b) macroscopic; (c) symbolic, macroscopic; (d) microscopic

Macroscopic. The heat required is determined from macroscopic properties.

Liquids can change their shape (flow); solids can’t. Gases can undergo large volume changes as pressure changes; liquids do not. Gases flow and change volume; solids do not.

The mixture can have a variety of compositions; a pure substance has a definite composition. Both have the same composition from point to point.

Molecules of elements contain only one type of atom; molecules of compounds contain two or more types of atoms. They are similar in that both are comprised of two or more atoms chemically bonded together.

Answers will vary. Sample answer: Gatorade contains water, sugar, dextrose, citric acid, salt, sodium chloride, monopotassium phosphate, and sucrose acetate isobutyrate.

(a) element; (b) element; (c) compound; (d) mixture; (e) compound; (f) compound; (g) compound; (h) mixture

In each case, a molecule consists of two or more combined atoms. They differ in that the types of atoms change from one substance to the next.

Gasoline (a mixture of compounds), oxygen, and to a lesser extent, nitrogen are consumed. Carbon dioxide and water are the principal products. Carbon monoxide and nitrogen oxides are produced in lesser amounts.

(a) Increased as it would have combined with oxygen in the air thus increasing the amount of matter and therefore the mass. (b) 0.9 g

(a) 200.0 g; (b) The mass of the container and contents would decrease as carbon dioxide is a gaseous product and would leave the container. (c) 102.3 g

(a) physical; (b) chemical; (c) chemical; (d) physical; (e) physical

physical

The value of an extensive property depends upon the amount of matter being considered, whereas the value of an intensive property is the same regardless of the amount of matter being considered.

Being extensive properties, both mass and volume are directly proportional to the amount of substance under study. Dividing one extensive property by another will in effect “cancel” this dependence on amount, yielding a ratio that is independent of amount (an intensive property).

about a yard

(a) kilograms; (b) meters; (c) meters/second; (d) kilograms/cubic meter; (e) kelvin; (f) square meters; (g) cubic meters

(a) centi-, $\times$ 10⁻²; (b) deci-, $\times$ 10⁻¹; (c) Giga-, $\times$ 10⁹; (d) kilo-, $\times$ 10³; (e) milli-, $\times$ 10⁻³; (f) nano-, $\times$ 10⁻⁹; (g) pico-, $\times$ 10⁻¹²; (h) tera-, $\times$ 10¹²

(a) m = 18.58 g, V = 5.7 mL; (b) d = 3.3 g/mL; (c) malachite (basic copper carbonate, d = 3.25—4.10 g/mL).

(a) displaced water volume = 2.8 mL; (b) displaced water mass = 2.8 g; (c) The block mass is 2.76 g, essentially equal to the mass of displaced water (2.8 g) and consistent with Archimedes’ principle of buoyancy.

(a) 7.04 $\times$ 10²; (b) 3.344 $\times$ 10⁻²; (c) 5.479 $\times$ 10²; (d) 2.2086 $\times$ 10⁴; (e) 1.00000 $\times$ 10³; (f) 6.51 $\times$ 10⁻⁸; (g) 7.157 $\times$ 10⁻³

(a) exact; (b) exact; (c) uncertain; (d) exact; (e) uncertain; (f) uncertain

(a) two; (b) three; (c) five; (d) four; (e) six; (f) two; (g) five

(a) 0.44; (b) 9.0; (c) 27; (d) 140; (e) 1.5 $\times$ 10⁻³; (f) 0.44

(a) 2.15 $\times$ 10⁵; (b) 4.2 $\times$ 10⁶; (c) 2.08; (d) 0.19; (e) 27,440; (f) 43.0

(a) Archer X; (b) Archer W; (c) Archer Y

(a) $\frac{\text{1.0936 yd}}{\text{1 m}}$; (b) $\frac{\text{0.94635 L}}{\text{1 qt}}$; (c) $\frac{\text{2.2046 lb}}{\text{1 kg}}$

$\begin{array}{c}\frac{\text{2.0 L}}{\text{67.6 fl oz}}=\frac{\text{0.030 L}}{\text{1 fl oz}}\end{array}$

Only two significant figures are justified.

68–71 cm; 400–450 g

355 mL

8 $\times$ 10⁻⁴ cm

yes; weight = 89.4 kg

5.0 $\times$ 10⁻³ mL

(a) 1.3 $\times$ 10⁻⁴ kg; (b) 2.32 $\times$ 10⁸ kg; (c) 5.23 $\times$ 10⁻¹² m; (d) 8.63 $\times$ 10⁻⁵ kg; (e) 3.76 $\times$ 10⁻¹ m; (f) 5.4 $\times$ 10⁻⁵ m; (g) 1 $\times$ 10¹² s; (h) 2.7 $\times$ 10⁻¹¹ s; (i) 1.5 $\times$ 10⁻⁴ K

45.4 L

1.0160 $\times$ 10³ kg

(a) 394 ft; (b) 5.9634 km; (c) 6.0 $\times$ 10²; (d) 2.64 L; (e) 5.1 $\times$ 10¹⁸ kg; (f) 14.5 kg; (g) 324 mg

0.46 m; 1.5 ft/cubit

Yes, the acid’s volume is 123 mL.

62.6 in (about 5 ft 3 in.) and 101 lb

(a) 3.81 cm $\times$ 8.89 cm $\times$ 2.44 m; (b) 40.6 cm

2.70 g/cm³

(a) 81.6 g; (b) 17.6 g

(a) 5.1 mL; (b) 37 L

5371 °F, 3239 K

−23 °C, 250 K

−33.4 °C, 239.8 K

113 °F