Mastering Chemistry: Chapter 1 Homework

Classify each statement as an observation, a law, or a theory.
Drag the appropriate items to their respective bins.:

(A): Neon does not react with sodium at room temperature and pressure.

(B): Chlorine reacts violently with sodium at room temperature and pressure.

(C): If elements are listed in order of increasing mass of their atoms, their chemical reactivity follows a repeating pattern.

(D): The reactivity of elements depends on the arrangement of their electrons.

Observation: (A), (B)

Law: (C)

Theory: (D)

Classify each of the following molecular diagrams as a pure substance or a mixture.

Figure 1: (a), Figure 2: (b), Figure 3: (c), Figure 4: (d)

Pure Substance: (a), (c), (d)

Mixture: (a)

Classify each substance as an element or a compound.

Figure 1: (a), Figure 2: (b), Figure 3: (c), Figure 4: (d)

Element: (a)

Compound: (d), (c)

Classify each of the following changes as physical or chemical.
Drag the appropriate items to their respective bins.

(A): A platinum ring becomes dull because of continued abrasion.

(B): Sugar dissolves in water.

(C): Sugar burns when heated on a skillet.

(D): A silver surface becomes tarnished after exposure to air for a long period of time.

Physical: (A), (B)

Chemical: (C), (D)

Correctly identify the images that accurately represent each sample of matter: a solid element, a liquid compound, and a heterogeneous mixture.
Drag the appropriate images to their respective targets. Not all images will be used.

Solid element: *looks like black circles that are pushed close together*

Liquid element: *looks like a bunch of pairs of black and white circles joined together with some space in between the other pairs*

Heterogeneous mixture:
*looks like a bunch of circles all pushed close together, but some are white and some are black*

Correctly identify the images that depict a liquid compound undergoing a physical change (clearly showing before and after).
Drag the appropriate images to their respective targets. Not all images will be used.

Liquid compound physical change:

box on the left:
*looks like a bunch of pairs of black and white circles joined together with some space in between the different pairs*

box on the right:
*looks like a few of pairs of black and white circles joined together with A LOT of space in between the different pairs*

Correctly identify the images that depict a solid element undergoing a chemical change (clearly showing before and after).
Drag the appropriate images to their respective targets. Not all images will be used.

Solid element change:

box on the left:
*looks like black circles that are pushed close together*

box in the middle:
*looks like white circles that are pushed close together*

box of the right:
*looks like a bunch of pairs of black and white circles joined together with some space in between the different pairs*

km (kilometers)
Express your answer using six significant figures.

255024 mm = 255.024 km

Mm (megameters)
Express your answer using six significant figures.

255024 mm = 0.255024 Mm

mm (millimeters)
Express your answer using six significant figures.

255024 mm = 2.55024 × 10^8 mm

cm (centimeters)
Express your answer using six significant figures.

255024 mm = 2.55024 × 10^7 cm

How many 1-cmcm cubes would it take to construct a cube that is 4 cmcm on edge?
Express your answer using two significant figures.

64 cubes

What is the mass in gg of 429 mL of ethylene glycol?
Express your answer using three significant figures.

m = 476 g

What is the volume in LL of 3.8 kgkg of ethylene glycol?
Express your answer using two significant figures.

m = 476 g

Classify each of the following as an observation, a law, or a theory.

(a) All matter is made of tiny, indestructible particles called atoms.

(b) When iron rusts in a closed container, the mass of the container and its contents does not change.

(c) In chemical reactions, matter is neither created nor destroyed.

(d) When a match burns, heat is evolved.

Observation: (b) (d)

Law: (c)

Theory: (a)

If methyl alcohol boils at 84 ∘H, what is its boiling point on the Jekyll scale?
Express your answer using two significant figures.

t = 73 ∘J

The value of the Euro is currently $1.28 U.S. and the price of 1 liter of gasoline in France is 1.41 Euro. What is the price of 1 gallon of gasoline in U.S. dollars in France?

6.83 $U.S./gallon

Perform the following calculations to the correct number of significant figures.

A.) (24.3782×2.12)+313.30 = ...

B.) (85.6−24.641)÷0.0040 = ...

C.) (542÷982.4)+5.73 = ...

A.) 3.650 * 10^2

B.) 1.5 * 10^4

C.) 6.28 * 10^0

Table salt contains 39.33 gg of sodium per 100 gg of salt. The UU.SS. Food and Drug Administration (FDA) recommends that adults consume less than 2.40 gg of sodium per day. A particular snack mix contains 1.29 gg of salt per 100 gg of the mix. What mass of the snack mix can you consume and still be within the FDA limit?

m = 473 g

A proton has a radius of approximately 1.0×10−13 cm and a mass of 1.7×10−24 g. Determine the density of a proton. For a sphere V=(4/3)πr^3. Express the density to two significant figures.

ρ = 4.1 × 10^14 g/cm^3

A solid aluminum sphere has a mass of 81 g. Use the density of aluminum to find the radius of the sphere in inches.
Express your answer using two significant figures.

r = 7.6 x 10^-1

How many cubic centimeters are there in 2.11 yd^3 ?
Express the volume in cubic centimeters to three significant figures.

volume = 1.61 × 106 cm^3

Section 1.7 showed that in 1997 Los Angeles County air had carbon monoxide (CO)(CO) levels of 15.0 ppm. An average human inhales about 0.50 L of air per breath and takes about 20 breaths per minute.
How many milligrams of carbon monoxide does the average person inhale in an 9 hour period for this level of carbon monoxide pollution? Assume that the carbon monoxide has a density of 1.2 g/L. (Hint: 15.0 ppm CO means 15.0 LCO per 106L air.)
Express your answer using two significant figures.

m = 97 mg