Q: Convert 0.00056 kg to scientific notation with the correct number of significant figures.

$$5.6 \times 10$$^{-4}$$\ \mathrm{kg}$$

Question 1

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture in which the composition is uniform throughout, such as saline solution.

Question 2

Which of the following is a chemical change?

Accepted Answer

Burning a wood log in a fireplace.

Question 3

What is the correct chemical symbol for gold?

Accepted Answer

Au

Question 4

Which group on the periodic table contains the noble gases?

Accepted Answer

Group 18 (8A)

Question 5

A sample of a compound contains 2 hydrogen atoms and 1 oxygen atom per molecule. What is the chemical formula for this compound?

Accepted Answer

$$\mathrm{H_2O}$$

Question 6

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

Accepted Answer

Shredding a piece of paper.

Question 7

What is the density of a substance if a 50.0 g sample occupies a volume of 20.0 mL?

Accepted Answer

$$2.50\ \mathrm{g/mL}$$

Question 8

Convert 0.00056 kg to scientific notation with the correct number of significant figures.

Accepted Answer

$$5.6 	imes 10$$^{-4}$$\ \mathrm{kg}$$

Question 9

Which of the following is an exact number?

Accepted Answer

The number of students in a classroom.

Question 10

A patient’s body temperature is measured as 39.0 $$^{\circ}C. $$What is this temperature in Kelvin?

Accepted Answer

$$312.2\ \mathrm{K}$$

Question 11

Which of the following is the correct balanced equation for the combustion of methane ($$\mathrm{CH_4$}) in $$oxygen?

Accepted Answer

$$\mathrm{CH_4$} + 2\mathrm{O_2$} \rightarrow \mathrm{CO_2$} + 2\mathrm{H_2O}$$

Question 12

Which prefix multiplier represents $$10^{-3}$$?

Accepted Answer

milli-

Question 13

A nurse needs to administer 250 mg of a medication. The available tablets are 0.50 g each. How many tablets should the nurse give?

Accepted Answer

0.5 tablets

Question 14

Which of the following statements about significant figures is correct?

Accepted Answer

When multiplying or dividing, the answer should have the same number of significant figures as the measurement with the fewest significant figures.

Question 15

Which of the following is a compound?

Accepted Answer

Table salt ($$\mathrm{NaCl})$$

Question 16

A solution is prepared by dissolving 10.0 g of NaCl in enough water to make 250.0 mL of solution. What is the concentration of NaCl in g/mL?

Accepted Answer

$$0.0400\ \mathrm{g/mL}$$

Question 17

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

Accepted Answer

Accuracy is how close a measurement is to the true value, while precision is how close repeated measurements are to each other.

Question 18

A 24.8 g sample of metal absorbs 275 J of energy, causing its temperature to rise from 20.2 $$^{\circ}C to 24.5$$ $$^{\circ}C. $$What is the specific heat ($$c) of $$the metal?

Accepted Answer

$$2.87\ \mathrm{J/(g\cdot ^\circ C)}$$

Question 19

Which of the following is NOT a property of metals?

Accepted Answer

They are found on the right side of the periodic table.

Chapter 1: Chemistry Basics – Matter and Measurement (GOB Chemistry Study Notes)

Guida di studio - Domande di pratica

Study guide - Flashcard