Question 1

Which of the following best describes the difference between a scientific law and a scientific theory?

Accepted Answer

A scientific law is a summary of observed behavior, while a theory is an explanation based on evidence and reasoning.

Question 2

Which of the following is the correct SI unit and prefix for a measurement of $$2.5 	imes 10$$^{-6}$$ meters?

Accepted Answer

$$2.5$$ micrometers ($$\mum)$$

Question 3

A student measures the mass of a sample three times and records: $$5.12 g$$, $$5.13 g$$, and $$5.11 g. $$The true mass is $$5.50 g. $$Which statement best describes the accuracy and precision of these measurements?

Accepted Answer

Low accuracy, high precision

Question 4

Which of the following numbers has exactly three significant figures?

Accepted Answer

$$55.0$$

Question 5

Convert $$2.13$$ nanometers (nm) to millimeters (mm).

Accepted Answer

$$2.13 	imes 10$$^{-6}$$ mm

Question 6

A European car is advertised as having a gas mileage of $$15 km/L. $$What is this rating in miles per gallon? (Given: $$1 m$$ = $$1.094 yd$$, $$1760 yd$$ = $$1$$ mile, $$1.06 qt$$ = $$1 L$$, $$4 qt$$ = $$1$$ gal)

Accepted Answer

$$35.4 mi/$$gal

Question 7

Which of the following is an example of a derived SI unit?

Accepted Answer

Joule (J)

Question 8

A vessel contains $$4.67 L of $$bromine with a density of $$3.10 g/cm$^3. $$What is the mass of bromine in kilograms?

Accepted Answer

$$14.5 kg$$

Question 9

Which of the following best describes the process of dimensional analysis?

Accepted Answer

Using conversion factors to change a given unit to a needed unit, ensuring units cancel appropriately.

Question 10

A sunscreen contains $$2.50\%$$ benzyl salicylate by mass. If a crate contains $$2.0$$ crates, each with $$16$$ boxes of $$144$$ tubes, and each tube is $$4.0 oz$$, how many kilograms of benzyl salicylate are needed? ($$1 oz$$ = $$28.35 g)$$

Accepted Answer

$$8.2 kg$$

Question 11

Which of the following is the correct formula for converting Celsius to Kelvin?

Accepted Answer

$$K = ^\circ C + 273.15$$

Question 12

A package of aluminum foil is $$66.7 yd $$long, $$13 in $$wide, and $$0.000762 mm $$thick. If aluminum has a density of $$2.70 g/mL$$, what is the mass, in grams, of the foil? ($$1 yd$$ = $$3 ft$$, $$1 in$$ = $$2.54 cm$$, $$1 mL$$ = $$1 cm$^3)$$

Accepted Answer

$$504 g$$

Question 13

Which of the following statements about significant figures is correct?

Accepted Answer

Leading zeros are never significant.

Question 14

Which of the following is the correct result for $$2.334 mL$$ $$+ 0.31 mL$$, reported to the correct number of significant figures?

Accepted Answer

$$2.64 mL$$

Question 15

Which of the following is an example of an exact number?

Accepted Answer

The number of students in a classroom

Question 16

A graduated cylinder contains $$11.2 mL of $$water. If $$5.25 g of $$pure silver (density $$10.5 g/cm$^3) is $$added, to what volume will the water rise?

Accepted Answer

$$11.7 mL$$

Question 17

Which of the following is the correct conversion factor for converting inches to centimeters?

Accepted Answer

$$1 in = 2.54$ cm

Question 18

Which of the following best describes a hypothesis in the scientific method?

Accepted Answer

A tentative explanation that can be tested by experiments.

Question 19

Which of the following is the correct SI unit for energy?

Accepted Answer

Joule (J)

Question 20

Which of the following is the correct result for $$2.334 cm$$ $$	imes 0.320 cm$$ $$	imes 1.2 cm$$, reported to the correct number of significant figures?

Accepted Answer

$$0.90 cm$^3$$

Foundational Topics in Chemistry: Measurement, Units, and Problem Solving

Guida di studio - Domande di pratica

Study guide - Flashcard