Chapter 3 Lesson 2: Units of Measurement

Question 1

What makes metric units easy to use?

Answer 1

All metric units are based on multiples of 10. As a result, you can convert between units easily.

Question 2

SI unit of Length

Answer 2

Meter (m)

Question 3

SI unit of Mass

Answer 3

Kilogram (kg)

Question 4

SI unit of Temperature

Answer 4

kelvin (k)

Question 5

SI unit of time

Answer 5

Second (s)

Question 6

SI unit of (amount of substance)

Answer 6

Mole (mol)

Question 7

Mega

Answer 7

Symbol: M
Meaning: 1 million times larger than the unit it precedes
Factor: 10 to the power of 6

Question 8

kilo

Answer 8

Symbol: k
Meaning: 1000 times larger than the unit it precedes
Factor: 10 to the power of 3

Question 9

deci

Answer 9

Symbol: d
Meaning: 10 times smaller than the unit it precedes
Factor: 10 to the power of -1

Question 10

centi

Answer 10

Symbol: C
Meaning: 100 times smaller than the unit it precedes
Factor: 10 to the power of -2

Question 11

milli

Answer 11

Symbol: m
Meaning: 1000 times smaller than the unit it precedes
Factor: 10 to the power of -3

Question 12

SI unit of (volume)

Answer 12

cubic meter

Question 13

Liter

Answer 13

Symbol: L
Relationship: base unit

Question 14

Milliliter

Answer 14

Symbol: mL
Relationship: 1000 mL = 1 L
divide by 1000 to get liter

Question 15

Cubic centimeter

Answer 15

Symbol: cm3
Relationship: 1 cm3 = 1 mL
multiply by 1000

Question 16

gram (g)

Answer 16

1/1000 of a kilogram

Question 17

Kilogram (base unit)

Answer 17

Symbol: kg
Relationship: 1 kg = 1000 g

Question 18

Gram

Answer 18

Symbol: g
Relationship: 1 g = 10 to the power of -3 kg

Question 19

milligram

Answer 19

Symbol: mg
Relationship: 1000mg = 1 g

Question 20

Weight

Answer 20

is a force that measures the pull on a given mass by gravity.

Weight, a measure of force, is different from mass, which is a measure of the quantity of matter.

The weight of an object can change with its location.

Question 21

energy

Answer 21

The capacity to do work or to produce heat

Question 22

The SI unit of energy

Answer 22

joule (J)

Question 23

calorie (cal)

Answer 23

One calorie (cal) is the quantity of heat that raises the temperature of 1 g of pure water by 1°C.

Question 24

1 Joule

Answer 24

= 0.2390 cal

Question 25

1 calorie

Answer 25

= 4.184 J

Question 26

temperature scales

Answer 26

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Question 27

What temperature units do scientists commonly use?

Answer 27

Scientists commonly use two equivalent units of temperature, the degree Celsius and the kelvin.

Question 28

Temperature

Answer 28

is a measure of how hot or cold an object is. An object’s temperature determines the direction of heat transfer. When two objects at different temperatures are in contact, heat moves from the object at the higher temperature to the object at the lower temperature.

Question 29

Celsius scale

Answer 29

sets the freezing point of water at 0°C and the boiling point of water at 100°C.

Question 30

Kelvin scale

Answer 30

the freezing point of water is 273.15 kelvins (K), and the boiling point is 373.15 (K).

Question 31

The zero point on the Kelvin scale, 0 K, or absolute zero, is equal to –273.15°C.

Answer 31

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Question 32

converting kelvin to celsius

Answer 32

``` k= c + 273 c = k - 273 ```

Question 33

What determines the density of a substance?

Answer 33

Density is an intensive property that depends only on the composition of a substance, not the size of the sample.

Question 34

Relationship of density.

Answer 34

The relationship between an object’s mass and its volume tells you whether it will float or sink. This relationship is called density

Question 35

Density

Answer 35

is the ratio of the mass of an object to its volume.

Question 36

The SI unit of density

Answer 36

kilograms per cubic meter (kg/m3).

Question 37

Density = mass/volume

Answer 37

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