Question 1

A NASA spacecraft was lost due to a unit conversion error between metric and English units. If a force was calculated in Newtons but entered in pound-seconds, which of the following best explains the consequence of this mistake?

Accepted Answer

The spacecraft's trajectory correction was incorrect, causing it to enter the Martian atmosphere at the wrong angle and crash.

Question 2

Which of the following is NOT a base unit in the International System of Units (SI)?

Accepted Answer

Gram

Question 3

A student measures the length of a table as 2.50 meters. Which part of this measurement reflects the precision of the instrument used?

Accepted Answer

The number '2.50'

Question 4

Which of the following numbers has exactly four significant figures?

Accepted Answer

$$2.050$$

Question 5

Convert 105 km/h to meters per second. Use $$1 \mathrm{~km} = 1000 \mathrm{~m}$$ and $$1 \mathrm{~h} = 3600 \mathrm{~s}. $$What is the correct answer, rounded to three significant figures?

Accepted Answer

$$29.2 \mathrm{~m/s}$$

Question 6

Which temperature conversion equation is correct for converting Celsius to Kelvin?

Accepted Answer

$$T(K) = t(\mathrm{~°C}) + 273.15$$

Question 7

A platinum sample has a density of $$21.5 \mathrm{~g/cm^3$}$$ and a volume of $$4.49 \mathrm{~cm^3$}. $$What is its mass in grams?

Accepted Answer

$$96.5 \mathrm{~g}$$

Question 8

Which of the following statements about significant figures is TRUE?

Accepted Answer

Zeros at the end of a number are significant only if there is a decimal point.

Question 9

A student calculates $$52 	imes 12.054 	imes 0.53. $$How many significant figures should the answer have?

Accepted Answer

2

Question 10

Which of the following is an intensive property?

Accepted Answer

Density

Question 11

A sample of mercury has a density of $$13.6 \mathrm{~g/cm^3$}. $$What is the mass in grams of $$95 \mathrm{~mL} of $$mercury? (Assume $$1 \mathrm{~mL} = 1 \mathrm{~cm^3$})$$

Accepted Answer

$$1292 \mathrm{~g}$$

Question 12

Which of the following is the correct scientific notation for the number 0.0000000000000000000000199?

Accepted Answer

$$1.99 	imes 10$$^{-23}$$

Question 13

Which conversion factor would you use to convert inches to centimeters?

Accepted Answer

$$1 \mathrm{~in} = 2.54 \mathrm{~cm}$$

Question 14

Which prefix multiplier represents $$10^{-6} in $$the metric system?

Accepted Answer

micro-

Question 15

A student wants to convert $$325 \mathrm{~mg} of $$aspirin to grams. What is the correct answer?

Accepted Answer

$$0.325 \mathrm{~g}$$

Question 16

Which of the following best describes an endothermic process?

Accepted Answer

Heat transfers from the surroundings to the system, and the temperature of the surroundings decreases.

Question 17

How many significant figures are in the number $$0.00801008$$?

Accepted Answer

6

Question 18

Which equation correctly relates kinetic energy to mass and velocity?

Accepted Answer

$$KE = \frac{1}{2}mv^2$

Question 19

A student needs to convert $$76 \mathrm{~yards} to $$centimeters. Which sequence of conversion factors should be used?

Accepted Answer

$$\mathrm{yards} \rightarrow \mathrm{meters} \rightarrow \mathrm{centimeters}$$

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

Guida di studio - Domande di pratica

Study guide - Flashcard