Q: Which of the following numbers is correctly written in scientific notation?

$$0.00052 = 5.2 \times 10$$^{-4}$$

Q: Which of the following is the correct formula for density?

$$\text{Density} = \frac{\text{mass}}{\text{volume}}$$

Question 1

On December 11, 1999, NASA lost the Mars Climate Orbiter due to a unit conversion error. Which of the following best explains the scientific lesson from this event?

Accepted Answer

Consistent and correct use of units is critical in scientific calculations.

Question 2

Which of the following numbers is correctly written in scientific notation?

Accepted Answer

$$0.00052 = 5.2 	imes 10$$^{-4}$$

Question 3

How many significant figures are in the measurement 0.00340?

Accepted Answer

3

Question 4

Which of the following best describes the rule for addition and subtraction with significant figures?

Accepted Answer

The answer should have as many decimal places as the number with the fewest decimal places.

Question 5

A student multiplies $$3.45 	imes 2.1$$ and gets $$7.245. $$What is the correct answer with the proper number of significant figures?

Accepted Answer

$$7.2$$

Question 6

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

Accepted Answer

kilogram (kg)

Question 7

Convert $$2.54$$ centimeters to inches. (Given: $$1$$ inch $$= 2.54 cm)$$

Accepted Answer

$$1$$ inch

Question 8

A liquid has a mass of $$137.2 g $$and a volume of $$51.6 mL. $$What is its density?

Accepted Answer

$$2.66$$ 	ext{ g/mL}$

Question 9

Which of the following best describes the Law of Conservation of Mass?

Accepted Answer

Matter is neither created nor destroyed in a chemical reaction.

Question 10

Which of the following is a derived SI unit?

Accepted Answer

cubic centimeter $$(cm^3)$$

Question 11

A sample of gasoline has a density of $$0.69 g/mL. $$What is the mass of $$750 mL of $$gasoline?

Accepted Answer

$$517.5$$ 	ext{ g}$

Question 12

Which of the following is NOT a common SI base unit?

Accepted Answer

Liter (L)

Question 13

Which of the following statements about energy is correct?

Accepted Answer

Energy is the capacity to do work or produce heat.

Question 14

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

Accepted Answer

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

Question 15

Which of the following best describes a mixture?

Accepted Answer

A combination of two or more substances that retain their individual properties.

Question 16

Which of the following is an example of a physical change?

Accepted Answer

Dissolving sugar in water

Question 17

Which of the following is the correct way to express $$0.0000973 in $$scientific notation?

Accepted Answer

$$9.73 	imes 10$$^{-5}$$

Question 18

Which of the following best describes the difference between accuracy and precision?

Accepted Answer

Accuracy is how close measurements are to the true value; precision is how close measurements are to each other.

Question 19

A temperature is measured as $$25.0^\circ C. $$What is this temperature in Kelvin?

Accepted Answer

$$298.2$$ 	ext{ K}$

Question 20

Which of the following is the correct formula for density?

Accepted Answer

$$	ext{Density} = \frac{	ext{mass}}{	ext{volume}}$$

General Chemistry Study Notes: Measurement, Matter, and Energy

Guida di studio - Domande di pratica

Study guide - Flashcard