Question 1

Which of the following best describes the difference between a compound and a homogeneous mixture?

Accepted Answer

A compound contains two or more elements chemically combined in a fixed ratio, while a homogeneous mixture contains two or more substances physically mixed with uniform composition.

Question 2

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

Accepted Answer

Water and copper

Question 3

Which of the following statements about solids is correct?

Accepted Answer

Solids have a definite shape and volume because their particles are close together in a fixed arrangement.

Question 4

A sample of matter has a definite volume but takes the shape of its container. Which state of matter is this?

Accepted Answer

Liquid

Question 5

Which of the following is a physical change?

Accepted Answer

Ice melting in a glass of water

Question 6

Which of the following is a chemical property?

Accepted Answer

The ability of iron to rust when exposed to oxygen

Question 7

Convert $$-15\ ^\circ\mathrm{F} to $$Celsius using the formula $$T_\mathrm{C} = \frac{5}{9}(T_\mathrm{F} - 32). $$What is the temperature in Celsius?

Accepted Answer

$$-26\ ^\circ\mathrm{C}$$

Question 8

If your body temperature is $$37\ ^\circ\mathrm{C}$$, what is it in Kelvin? (Use $$T_\mathrm{K} = T_\mathrm{C} + 273.15)$$

Accepted Answer

$$310.15\ \mathrm{K}$$

Question 9

How many calories are obtained from a pat of butter if it provides $$150\ \mathrm{J} of $$energy when metabolized? (Use $$1\ \mathrm{cal} = 4.184\ \mathrm{J})$$

Accepted Answer

$$35.9\ \mathrm{cal}$$

Question 10

What is the specific heat ($$c) if$$ $$24.8\ \mathrm{g} of a $$metal absorbs $$275\ \mathrm{J} of $$energy and the temperature rises from $$20.2\ ^\circ\mathrm{C} to$$ $$24.5\ ^\circ\mathrm{C}$$? (Use $$q = mc\Delta T)$$

Accepted Answer

$$2.60\ \mathrm{J}/(\mathrm{g}\ ^\circ\mathrm{C})$$

Question 11

How many Joules are needed to melt $$32.0\ \mathrm{g} of $$ice at $$0\ ^\circ\mathrm{C}$$? (Heat of fusion for water is $$334\ \mathrm{J}/\mathrm{g})$$

Accepted Answer

$$10,688\ \mathrm{J}$$

Question 12

How many kilojoules are released when $$50.0\ \mathrm{g} of $$steam condenses at $$100\ ^\circ\mathrm{C}$$? (Heat of condensation for water is $$-2260\ \mathrm{J}/\mathrm{g})$$

Accepted Answer

$$-113\ \mathrm{kJ}$$

Question 13

A plateau (horizontal line) on a heating curve represents:

Accepted Answer

A constant temperature and a change of state

Question 14

Which of the following best describes the energy in gasoline stored in a car's gas tank?

Accepted Answer

Potential energy

Question 15

Which of the following is an example of kinetic energy?

Accepted Answer

A person mowing the lawn

Question 16

Which of the following is NOT a physical property of copper?

Accepted Answer

Ability to react with oxygen to form copper oxide

Question 17

Which of the following best explains why sand in the desert is hot during the day and cool at night?

Accepted Answer

Sand has a low specific heat, so it heats up and cools down quickly.

Question 18

You have $$175\ \mathrm{g} of $$steam at $$100.0\ ^\circ\mathrm{C}. $$How many kilojoules are lost when the steam condenses and then freezes at $$0.0\ ^\circ\mathrm{C}$$? (Heat of condensation: $$-2260\ \mathrm{J}/\mathrm{g}$$, Heat of crystallization: $$-336\ \mathrm{J}/\mathrm{g}$$, Specific heat of water: $$4.184\ \mathrm{J}/(\mathrm{g}\ ^\circ\mathrm{C}))$$

Accepted Answer

$$-504.7\ \mathrm{kJ}$$

Matter, Its Classification, States, and Properties – GOB Chemistry Chapter 3 Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard