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Question 1

Metric system

Answer 1

• Mass is represented in gram (g), the length in meter (m) , and volume in liter (L)

Question 2

English system -

Answer 2

Weight is measured by the unit of pound (lb) , the length by the unit of yard (yd), and the volume by the unit of gallon (gal)

Question 3

SI system

Answer 3

(International System). Based on the metric system

Question 4

Metric system
? mm = 1 cm
? cm = 1 m
?m = 1 km

Answer 4

10 mm = 1 cm
100 cm = 1 m
1000m = 1 km

Question 5

The total number of digits used to express such a measurement is called the number of ..

Answer 5

significant figures

Question 6

how many significant figures in exact number?

Answer 6

have an infinite number of significant figures

Question 7

what is an exact number?

Answer 7

Determined by counting and not by using a measuring device

Question 8

Zeroes in the middle (significant or not)?

Answer 8

significant

Question 9

Zeroes at the beginning of a number (significant or not)?

Answer 9

not significant

Question 10

Zeroes at the end of a number( significant or not)

Answer 10

significant

Question 11

Mass is

Answer 11

is a measure of amount of matter in an object.

Question 12

Volume is

Answer 12

is the amount of space occupied by an object

Question 13

density is

Answer 13

an amount of mass is a given space (density=mass/volume)

Question 14

Chemistry : is the study of

Answer 14

matter

Question 15

Chemistry

Answer 15

Its chemical and physical properties.

Chemical and physical changes it undergoes.

Energy changes of these processes.

Question 16

matter is

Answer 16

Anything that occupies space and has mass

Question 17

matter Exists in three states

Answer 17

Solid
Liquid
Gas

Question 18

properties of a solid

Answer 18

Rigid
Fixed volume and shape
Slightly compressible

Question 19

properties of a solid

Answer 19

Rigid
Fixed volume and shape
Slightly compressible

Question 20

Properties of a Liquid

Answer 20

Definite volume
No specific shape (Assumes the shape of its container)
Slightly compressible

Question 21

Properties of a Gas

Answer 21

-No fixed volume or shape
(Takes on the shape and volume of its container)
-Highly compressible (Relatively easy to decrease the volume of a gas )

Question 22

The conversion of a substance from one state into another is known as

Answer 22

change of state.

Question 23

processes from solid to liquid

processes from liquid to gas

Answer 23

melting

evaporation

Question 24

gas to liquid called..

liquid to solid called..

Answer 24

condensation

freezing

Question 25

Physical Properties can be

Answer 25

- measured or obtained without changing the composition of the material. like to separate a mixture into pure compounds, but it will not break compounds into elements. - no chemical changes - reversible

Question 26

examples of physical properties

Answer 26

mass- density- texture- volume- magnetism- length- color

Question 27

what are intensive and extensive properties?

Answer 27

Intensive Property : Independent of the quantity of substance (Ex: color, hardness, melting, boiling point, density) Extensive Property: Depends on the quantity of the substance (Ex: mass, volume, length, weight)

Question 28

Separating mixture into pure compounds , changing physical properties by:

Answer 28

filtration - distillation - chromatography

Question 29

Chemical properties

Answer 29

-undergo chemical changes

Question 30

examples of chemical changes

Answer 30

``` flammability toxicity rust with oxygen react with finger and water radioactivity sensitivity to light ```

Question 31

chemical changes are

Answer 31

- irreversible | - a given substance becomes a new substance with different properties and composition

Question 32

chemical reaction

Answer 32

is a process of rearranging, replacing, or adding atoms to generate a new substance

Question 33

Pure Substance:

Answer 33

Involves one component. Sugar and water are pure substances. A pure substance can be a 1chemical compound or 1 element

Question 34

do pure substance can decompose to other substance?

Answer 34

no they can't decompose to other substances

Question 34

atom

Answer 34

is the smallest particle of an element that have the chemical properties of an element

Question 35

molecule

Answer 35

smallest unit of a compound, 2 or more atoms connected together it can be the same atom like O2

Question 36

Chemical Element:

Answer 36

substance whose atoms all have the same number of protons

Question 36

Chemical Compounds:

Answer 36

are composed of atoms chemically bonded to each other in fixed ratios and can be decomposed to those atoms

Question 36

matter

Answer 36

composed of tiny particles called atom

Question 37

mixture

Answer 37

more than one substance

Question 38

types of mixture

Answer 38

Homogeneous mixture (solution) and Heterogeneous mixture

Question 39

Heterogeneous mixture:

Answer 39

have many phases like sand in water - oil in water , non-uniform composition

Question 40

Homogeneous Mixture

Answer 40

have on phase , uniform composition like water and alcohol