Matter

Question 1

Physical Change

Answer 1

A Change that does not affect the chemical makeup of a substance or object

Question 2

Chemical Change

Answer 2

A change in the chemical makeup of a substance

Question 3

Chemical or Physical Change: Solid ice melts to create liquid water. Explain your reasoning.

Answer 3

Physical. The chemical composition of water is still the same. The only thing that changes is the physical shape.

Question 4

Chemical or Physical Change: An iron bicycle that is left in the rain rusts. Explain your reasoning.

Answer 4

Chemical. This is a chemical change because the bicycle is no longer “iron”. Because the iron combines with oxygen and moisture from the air to create the new substance “rust”.

Question 5

List the properties of Water.

Answer 5

• Colorless
• Odorless
• Melting point is at 0 degrees C
• Boiling point is at 100 degrees C
• Does not burn
• 11.2% H
• 88.8% O

Question 6

List the properties of Sugar (Sucrose).

Answer 6

• White crystals
• Odorless
• Begins to decompose at 160 degrees C, turning black and giving off water [Chemical change]
• Burns in air
• 6.4% H
• 42.1% C
• 51.5% O
• 57.3% O

Question 7

List the properties of Baking Soda (Sodium Bicarbonate).

Answer 7

• White Powder
• Odorless
• Decomposes at 270 degrees C giving off water and carbon dioxide [Chemical change]
• Does not burn
• 27.4% Na
• 1.2% H
• 14.3% C

Question 8

Which of the following are made of chemicals:

a) Hairspray
b) A goldfish
c) Paint
d) A watermelon

Answer 8

all

Question 9

Identify each of the following as a physical change or a chemical change:

a) A metal surface being ground
b) Fruit Ripening
c) Wood burning
d) A puddle evaporating

Answer 9

a) Physical
b) Chemical
c) Chemical
d) Physical

Question 10

Pure Substance

Answer 10

a substance that has a uniform chemical composition throughout

Question 11

mixture

Answer 11

a blend of two or more substances, each of which retains its chemical identity

Question 12

Pure substance or mixture: Sugar water

Answer 12

mixture

Question 13

Pure substances are classified into what two groups?

Answer 13

those that undergo a chemical breakdown to yield a simpler substance and those that can’t. [compounds and elements]

Question 14

Chemical compound

Answer 14

a pure substance that can be broken down into simpler substances by chemical reactions

Question 15

Reactant

Answer 15

a starting substance formed as a result of a chemical reaction

Question 16

Product

Answer 16

a substance formed as the result of a chemical reaction

Question 17

Chemical reaction

Answer 17

a process in which the identity and composition of one or more substances are changed

Question 18

element

Answer 18

a fundamental substance that can’t be broken down chemically into any simpler substance

Question 19

Compound or element: water

Answer 19

Compound. It can be broken down to hydrogen and oxygen

Question 20

Compound or element: gold

Answer 20

element. It can’t be broken down any further

Question 21

Matter can be divided into what two categories?

Answer 21

mixtures and pure substances

Question 22

Pure substances can be divided into what two categories?

Answer 22

compounds and elements

Question 23

Classify each of the following as a mixture or a pure substance?

a) concrete
b) helium in a balloon
c) a lead weight
d) wood

Answer 23

a) mixture
b) pure
c) pure
d) mixture

Question 24

Classify each of the following as a physical change or a chemical change?

a) separating a solid from a liquid by filtration
b) producing carbon dioxide gas and solid lime by heating limestone
c) mixing alchohol and water

Answer 24

a) physical
b) chemical
c) physical

Question 25

Metals

Answer 25

a malleable chemical with a lustrous appearance this is a good conductor of heat and electricity. They are typically solid at room temperature (exception: mercury)

Question 26

Nonmetal

Answer 26

an element that is a poor conductor of heat and electricity

Question 27

Metalloid

Answer 27

an element whose properties are intermediate between those of a metal and a nonmetal

Question 28

Which of the following is composed of chemical? a) rosebush b) substances that give roses their fragrance c) the earth in which the bush grows

Answer 28

a) b) c)

Question 29

Which of the following is a chemical change and physical change? a) boiling water b) decomposing water by passing an electric current through it c) dissolving sugar in water d) exploding of potassium metal when placed in water e) breaking of glass

Answer 29

``` a) b) c) d) e) ```

Question 30

Physical or chemical change: a) steam condensing b) milk souring c) ignition of matches d) breaking of a dinner plate e) nickel sticking to a magnet f) exploding of nitroglycerin

Answer 30

``` a) b) c) d) e) f) ```

Question 31

Mixture or Pure Substance: a) pea soup b) seawater c) contents of a propane tank (c3H8) d) urine e) lead f) multivitamin tablet

Answer 31

``` a) b) c) d) e) f) ```

Question 32

Mixture of pure substance: a) blood b) silicon c) dishwashing liquid d) toothpaste e) gold f) gaseous ammonia

Answer 32

``` a) b) c) d) e) f) ```