Question 1

The mass of a sample is 550 milligrams. Which of the following expresses that mass in kilograms?
A)5.5 × 10 8 kg
B)5.5 × 10 5 kg
C)5.5 × 10 −4 kg
D)5.5 × 10 −6 kg
E)5.5 × 10 −1 kg

Accepted Answer

To convert milligrams to kilograms, we need to divide by 1,000,000 (or move the decimal point 6 places to the left). Therefore, 550 milligrams is equal to 0.00055 kilograms, which can be expressed as 5.5 × 10^(-4) kilograms.

Question 2

The speed needed to escape the pull of Earth's gravity is 11.3 km/s. What is this speed in mi/h?
A)65,500 mi/h
B)25,300 mi/h
C)18,200 mi/h
D)1,090 mi/h
E)5.02 × 10−3 mi/h

Accepted Answer

To convert km/s to mi/h, we can use the following conversions:
1 km = 0.621371 mi
1 h = 3600 s

Therefore, 11.3 km/s can be converted as follows:
11.3 km/s * (0.621371 mi/km) * (3600 s/h) = 25,314 mi/h

The closest option to this answer is B) 25,300 mi/h.

Question 3

Which of the following is not an SI base unit?
A)Meter
B)Ampere
C)Second
D)Gram
E)Kelvin

Accepted Answer

The SI base units are the meter for length, kilogram for mass, second for time, ampere for electric current, kelvin for temperature, mole for amount of substance, and candela for luminous intensity. The gram is a derived unit of mass, equal to 1/1000th of a kilogram.

Question 4

At a pressure of one billionth (10⁻⁹) of atmospheric pressure, there are about 2.7 × 10¹⁰ molecules in one cubic centimeter of a gas. How many molecules is this per cubic meter? A)2.7 × 10 ¹⁶ B)2.7 × 10 ¹⁴ C)2.7 × 10 ¹² D)2.7 × 10 ⁸ E)2.7 × 10 ⁴

Accepted Answer

Since 1 cubic meter is equal to 10^6 cubic centimeters, to convert the number of molecules per cubic centimeter to per cubic meter, you multiply by 10^6. Therefore, 2.7 × 10^11 molecules/cm^3 becomes 2.7 × 10^(11+6) = 2.7 × 10^17 molecules/m^3.

Question 5

The density of mercury, the only metal to exist as a liquid at room temperature, is 13.6 g/cm³. What is that density in pounds per cubic inch? A)849 lb/in ³ B)491 lb/in ³ C)376 lb/in ³ D)0.491 lb/in ³ E)1.83 × 10 − 3 lb/in ³

Accepted Answer

To convert the density of mercury from g/cm^3 to lb/in^3, we use the conversion factors: 1 inch = 2.54 cm and 1 lb = 453.592 g. Therefore, $13.6 \, \text{g/cm}^3 = 13.6 \times \frac{1}{453.592} \, \text{lb/g} \times \left(\frac{2.54}{1}\right)^3 \, \text{cm}^3/\text{in}^3 \approx 0.491 \, \text{lb/in}^3$.

Question 6

A dictionary has the following definition for a word: "A tentative explanation that accounts for a set of facts." Which of the following words best fits that definition?
A)Theory
B)Hypothesis
C)Law
D)Experiment
E)Definition

Accepted Answer

The best fit for the definition is "hypothesis," as it specifically refers to a tentative explanation that has yet to be fully tested or proven. The other choices have slightly different meanings: a theory is a well-supported explanation for a set of facts, a law is a statement that describes a phenomenon observed in nature, an experiment is a scientific procedure designed to test a hypothesis or theory, and a definition is a statement that explains the meaning of a particular word or concept.

Question 7

Which of the following represents the largest volume?
A)10,000 µL
B)1000 pL
C)100 mL
D)10 nL
E)10 cm 3

Accepted Answer

100 mL is the largest volume among the given options. 10 cm³ is equivalent to 10 mL, 10,000 µL is equivalent to 10 mL, 10 nL is equivalent to 0.01 µL, and 1000 pL is equivalent to 0.001 µL.

Question 8

Given that 1 inch = 2.54 cm, 1 cm³ is equal to A)16.4 in ³. B)6.45 in ³. C)0.394 in ³. D)0.155 in ³. E)0.0610 in ³.

Accepted Answer

To convert cubic centimeters to cubic inches, use the conversion factor (1 inch = 2.54 cm) cubed: (1 cm)^3 = (1/2.54)^3 in^3 = 0.0610 in^3.

Question 9

A detailed explanation of natural phenomena that is generally accepted and has been extensively tested is called a
A)theory.
B)hypothesis.
C)law.
D)fact.
E)postulate.

Accepted Answer

A detailed explanation of natural phenomena that is generally accepted and has been extensively tested is called a theory. A hypothesis is a proposed explanation for a phenomenon that has not yet been extensively tested. A law is a description of a natural phenomenon that holds true under specific conditions but does not provide an explanation for why it occurs. A fact is a piece of information that is objectively true and can be independently verified. A postulate is a basic assumption that is taken to be true without proof.

Question 10

A large pizza has a diameter of 15 inches. Express this diameter in centimeters.
A)38 cm
B)24 cm
C)18 cm
D)9.3 cm
E)5.9 cm

Accepted Answer

To convert inches to centimeters, multiply by 2.54. So, 15 inches * 2.54 = 38 cm.

Question 11

The average distance between the Earth and the Moon is 240,000 miles. Express this distance in kilometers. A)6.1 × 10 ⁵ km B)5.3 × 10 ⁵ km C)3.9 × l0 ⁵ km D)1.5 × 10 ⁵ km E)9.4 × 10 ⁴ km

Accepted Answer

To convert miles to kilometers, multiply by 1.60934. Thus, 240,000 miles is approximately 240,000 × 1.60934 = 386,241.6 km, which is closest to 3.9 × 10^5 km.

Question 12

In an average year, the American chemical industry produces more than 9.5 million metric tons of sodium carbonate. Over half of this is used in the manufacture of glass while another third is used in the production of detergents and other chemicals. How many pounds of sodium carbonate are produced annually?
A)2.1 × 10 10 lb
B)4.3 × 10 9 lb
C)1.1 × 10 7 lb
D)2.2 × 10 6 lb
E)2.1 × 10 4 lb

Accepted Answer

To convert metric tons to pounds, use the conversion factor 1 metric ton = 2,204.62 pounds. Therefore, 9.5 million metric tons is equivalent to 9.5 million * 2,204.62 = 2.1 × 10^10 pounds.

Question 13

A dose of medication was prescribed to be 35 microliters. Which of the following expresses that volume in centiliters?
A)3.5 × 10 5 cL
B)3.5 × 10 4 cL
C)3.5 cL
D)3.5 × 10 −4 cL
E)3.5 × 10 −3 cL

Accepted Answer

To convert microliters to centiliters, we need to divide by 10^6 (since there are 10^6 microliters in a liter and 10^2 centiliters in a liter). 
35 microliters = 35/10^6 liters = 3.5 × 10^-5 liters 
3.5 × 10^-5 liters = 3.5 × 10^-3 centiliters (since we need to multiply by 10^2 to get from liters to centiliters). Therefore, the answer is E: 3.5 × 10^-3 cL.

Question 14

The average distance from Earth to the Sun is 150 megameters. What is that distance in meters?
A)1.5 × 10 8 m
B)1.5 × 10 6 m
C)1.5 × 10 5 m
D)1.5 × 10 3 m
E)1.5 × 10 −6 m

Accepted Answer

"Mega" means one million, so 150 megameters is equal to 150 million meters, or 1.5 × 10^8 meters. Choice A matches this value.

Question 15

The distance between carbon atoms in ethylene is 134 picometers. Which of the following expresses that distance in meters? A)1.34 × 10 ⁻¹³ m B)1.34 × 10 ⁻12 m C)1.34 × 10 ⁻¹⁰ m D)1.34 × 10 ⁻⁷ m E)1.34 × 10 ⁻⁶ m

Accepted Answer

To convert picometers to meters, we need to move the decimal point 12 places to the left (since there are 10^12 picometers in a meter).

Thus, the distance between carbon atoms in ethylene is:

134 pm = 134 x 10^-12 m = 1.34 x 10^-10 m

The only answer choice that matches this expression is C:

1.34 x 10^-10 m = 1.34 x 10^-1 * 10^-9 m = 1.34 x 10^-1 nm

Therefore, the correct answer is:

Answer: C

Question 16

You prepare 1000. mL of tea and transfer it to a 1.00-quart pitcher for storage. Which of the following statements is true?
A)The pitcher will be filled to 100% of its capacity with no tea spilled.
B)The pitcher will be filled to about 95% of its capacity.
C)The pitcher will be filled to about 50% of its capacity.
D)The pitcher will be completely filled and a small amount of tea will overflow.
E)The pitcher will be completely filled and most of the tea will overflow.

Accepted Answer

The answer of You prepare 1000. mL of tea and...

Question 17

The symbol for the SI base unit of mass is
A)mg.
B)g.
C)kg.
D)metric ton.
E)lb.

Accepted Answer

The SI base unit for mass is kilogram (kg). The other options are either subunits of kg (mg, g) or non-SI units (metric ton, lb).

Question 18

A scientist made careful measurements of the pressure and temperature of many different gases. Based on these measurements, he concluded that "the pressure of a fixed amount of gas, measured at constant volume, is directly proportional to its absolute temperature." This statement is best described as a
A)theory.
B)hypothesis.
C)law.
D)experiment.
E)definition.

Accepted Answer

The statement is a description of Boyle's law, which is a well-established principle in physics and chemistry that has been extensively observed and tested. Therefore, it is considered a scientific law.

Question 19

If the price of gold at the morning fixing in London was $5310 per lb, what would a kilogram of gold have cost in £ (pounds)? (Assume an exchange rate of $1.00 = £0.545)
A)£1310
B)£3510
C)£6370
D)£10400
E)£17100

Accepted Answer

1 lb = 0.453592 kg 
Therefore, the price of 1 kg of gold in USD would be: 
$5310/0.453592 = $11,700 per kg

Now, we use the exchange rate to convert USD to pounds: 
$1.00 = £0.545 
Therefore, 1kg of gold would cost: 
£11,700 x 0.545 = £6,370

So the answer is C.

Question 20

The area of a 15-inch pizza is 176.7 in². Express this area in square centimeters. A)1140. cm ² B)448.8 cm ² C)96.8 cm ² D)69.57 cm ² E)27.39 cm ²

Accepted Answer

To convert square inches to square centimeters, multiply the area in square inches by 6.4516 (since 1 square inch = 6.4516 square centimeters). Therefore, 176.7 in² * 6.4516 = 1140 cm².

Quiz 1: Keys to the Study of Chemistry: Definitions, Units, and Problem Solving

The mass of a sample is 550 milligrams. Which of the following expresses that mass in kilograms?

The speed needed to escape the pull of Earth's gravity is 11.3 km/s. What is this speed in mi/h?

Which of the following is not an SI base unit?

At a pressure of one billionth (10⁻⁹) of atmospheric pressure, there are about 2.7 × 10¹⁰ molecules in one cubic centimeter of a gas. How many molecules is this per cubic meter?

The density of mercury, the only metal to exist as a liquid at room temperature, is 13.6 g/cm³. What is that density in pounds per cubic inch?

A dictionary has the following definition for a word: "A tentative explanation that accounts for a set of facts." Which of the following words best fits that definition?

Which of the following represents the largest volume?

Given that 1 inch = 2.54 cm, 1 cm³ is equal to

A detailed explanation of natural phenomena that is generally accepted and has been extensively tested is called a

A large pizza has a diameter of 15 inches. Express this diameter in centimeters.

The average distance between the Earth and the Moon is 240,000 miles. Express this distance in kilometers.

A dose of medication was prescribed to be 35 microliters. Which of the following expresses that volume in centiliters?

The average distance from Earth to the Sun is 150 megameters. What is that distance in meters?

The distance between carbon atoms in ethylene is 134 picometers. Which of the following expresses that distance in meters?

You prepare 1000. mL of tea and transfer it to a 1.00-quart pitcher for storage. Which of the following statements is true?

The symbol for the SI base unit of mass is

If the price of gold at the morning fixing in London was $5310 per lb, what would a kilogram of gold have cost in £ (pounds) ? (Assume an exchange rate of $1.00 = £0.545)

The area of a 15-inch pizza is 176.7 in². Express this area in square centimeters.