Q: Which equation would you use to calculate the amount of heat required to warm a substance?

$$q = m \times c \times \Delta T$$

Question 1

Which of the following best describes a chemical change?

Accepted Answer

Iron rusting when exposed to air

Question 2

A sample of formaldehyde melts at $$-92\ ^\circ\mathrm{C}$$ and boils at $$-19\ ^\circ\mathrm{C}. $$What is its physical state at $$25\ ^\circ\mathrm{C}$$?

Accepted Answer

Gas

Question 3

Which of the following is a homogeneous mixture?

Accepted Answer

Salt completely dissolved in water

Question 4

How many atoms are present in one molecule of $$\mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6$$?

Accepted Answer

24

Question 5

Which of the following is the correct scientific notation for 0.0000782?

Accepted Answer

$$7.82 	imes 10$$^{-5}$$

Question 6

Convert 0.450 kg to grams using dimensional analysis.

Accepted Answer

450 g

Question 7

Which of the following measurements has three significant figures?

Accepted Answer

0.00450 g

Question 8

A patient weighs 154 lb. The prescribed dose is $$0.0200\ \mathrm{mg/kg}. $$How many milligrams should be administered? ($$1\ \mathrm{lb} = 0.454\ \mathrm{kg})$$

Accepted Answer

1.40 mg

Question 9

Which equation would you use to calculate the amount of heat required to warm a substance?

Accepted Answer

$$q = m 	imes c 	imes \Delta T$$

Question 10

How much heat (in J) is required to warm 50.0 g of water from $$20.0\ ^\circ\mathrm{C} to$$ $$30.0\ ^\circ\mathrm{C}$$? (Specific heat of water $$c = 4.184\ \mathrm{J}/(\mathrm{g}\cdot^\circ\mathrm{C}))$$

Accepted Answer

2.09 × $$10^3 J$$

Question 11

Which of the following statements about density is correct?

Accepted Answer

Density is mass divided by volume.

Question 12

A liquid has a mass of 45.0 g and a volume of 18.0 mL. What is its density?

Accepted Answer

2.50 g/mL

Question 13

Which of the following is a physical property?

Accepted Answer

Melting point

Question 14

Which of the following is the correct symbol for the element sodium?

Accepted Answer

Na

Question 15

Which of the following is an example of a heterogeneous mixture?

Accepted Answer

Chocolate chip cookies

Question 16

Convert 25.0 g of isopropyl alcohol (density $$0.7855\ \mathrm{g/mL}) to $$volume in mL.

Accepted Answer

31.8 mL

Question 17

Which of the following is the correct conversion from Celsius to Kelvin?

Accepted Answer

$$K = ^\circ\mathrm{C} + 273.15$$

Question 18

Which of the following is a correct statement about significant figures?

Accepted Answer

Leading zeros do not count as significant figures.

Question 19

Which of the following is the correct result (with proper significant figures) for $$5.19\ \mathrm{cm} 	imes 95.01\ \mathrm{cm} 	imes 0.10\ \mathrm{cm}$$?

Accepted Answer

49 cm³

Question 20

Which of the following is a chemical property?

Accepted Answer

Reactivity with oxygen

Chapter 1: Matter and Measurements – GOB Chemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard