Q: A sample of mercury has a density of $$13.6\ g/cm^3$. What is the mass in grams of 95$$\ mL$$ of mercury?

$$m = 13.6\ g/cm^3$ \times 95\ cm^3$ = 1292\ g$$

Q: Which of the following is the correct conversion factor to convert pound-seconds to newton-seconds, as required in the Mars Climate Orbiter disaster?

$$1\text{ pound} \cdot \text{second} = 1.45\text{ newton} \cdot \text{second}$$

Q: Which equation correctly converts Celsius to Fahrenheit?

$$T(\text{F}) = 1.8 \times T(\text{C}) + 32$$

Q: Which of the following is an exact value and therefore has an infinite number of significant figures?

1 mol = $$6.02 \times 10$$^{23}$$ units

Q: A student measures the mass of a sample as 56.0 g and its volume as 4.0 cm³. What is the density, reported with the correct number of significant figures?

$$\text{Density} = \frac{56.0\ g}{4.0\ cm^3$} = 14\ g/cm^3$

Question 1

Which of the following is a quantitative observation?

Accepted Answer

The temperature increased by 5.0°C.

Question 2

A measurement consists of two essential parts. What are they?

Accepted Answer

Number and unit

Question 3

Which SI base unit is used to measure the amount of substance?

Accepted Answer

Mole (mol)

Question 4

What is the temperature in Kelvin of a patient with a body temperature of 39.5°C?

Accepted Answer

$$T(K) = 39.5 + 273.15 = 312.65\ K$$

Question 5

Which temperature scale does NOT allow for negative values?

Accepted Answer

Kelvin

Question 6

Which metric prefix multiplier is most appropriate for reporting a measurement of $$5.57 	imes 10$$^{-6}$$\ m$$?

Accepted Answer

Micro

Question 7

How many significant figures are in the measurement 0.0600 g?

Accepted Answer

Three

Question 8

Which of the following numbers has ambiguous significant figures and should be written in scientific notation to clarify?

Accepted Answer

1200

Question 9

A graduated cylinder is marked every 0.1 mL. If the meniscus is between 4.5 and 4.6 mL, what is the correct way to report the measurement?

Accepted Answer

4.56 mL

Question 10

When multiplying and dividing measured values, how do you determine the number of significant figures in the answer?

Accepted Answer

By the value with the smallest number of significant figures

Question 11

A sample of mercury has a density of $$13.6\ g/cm^3$. What is the mass in grams of 95$$\ mL$$ of mercury?

Accepted Answer

$$m = 13.6\ g/cm^3$ 	imes 95\ cm^3$ = 1292\ g$$

Question 12

When copper is heated from room temperature to $$95^	ext{C}$$, what happens to its density?

Accepted Answer

The sample expands.

Question 13

Which of the following is an intensive property?

Accepted Answer

Density

Question 14

What type of energy is chemical energy?

Accepted Answer

Potential energy

Question 15

Which of the following is the correct conversion factor to convert pound-seconds to newton-seconds, as required in the Mars Climate Orbiter disaster?

Accepted Answer

$$1	ext{ pound} \cdot 	ext{second} = 1.45	ext{ newton} \cdot 	ext{second}$$

Question 16

The burning of natural gas in a stove is an example of which type of process, and what is the sign of the energy change?

Accepted Answer

Exothermic; negative

Question 17

Which equation correctly converts Celsius to Fahrenheit?

Accepted Answer

$$T(	ext{F}) = 1.8 	imes T(	ext{C}) + 32$$

Question 18

Which of the following is an exact value and therefore has an infinite number of significant figures?

Accepted Answer

1 mol = $$6.02 	imes 10$$^{23}$$ units

Question 19

A student measures the mass of a sample as 56.0 g and its volume as 4.0 cm³. What is the density, reported with the correct number of significant figures?

Accepted Answer

$$	ext{Density} = \frac{56.0\ g}{4.0\ cm^3$} = 14\ g/cm^3$

Essentials of Units, Measurements, and Problem Solving in General Chemistry

Guida di studio - Domande di pratica

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