Unit 6 Review

Question 1

How many other words can you think of that describe physical changes?

Answer 1

Crush
Mash
Split
Crack
Break
Spray

Question 2

What happens to water if you lower the temperature below zero degrees Celcius?

Answer 2

It freezes into solid ice.

Question 3

What happens to water when you boil it?

Answer 3

It evaporates into water vapor (gas)

Question 4

What are some other ways matter can change states?

Answer 4

Cooling gases often causes them to condense into liquids. Heating solids often causes them to melt into liquids

Question 5

True of False

A physical change does not change the type of molecules that make up the substance.

Answer 5

True

Question 6

You cut a piece of wood and sand it to make a model. What kind of change occurred?

Answer 6

Physical change

Question 7

Which choice describes a physical change?

Answer 7

Cutting down a tree
Melting ice cream
Making lemonade from crystals

Question 8

Which change is likely to be a physical to an object?

Answer 8

The shape of the object changed

Question 9

What type of change will occur when the warm sun reaches icicles hanging from a rooftop?

Answer 9

Physical change

Question 10

The shoelaces on Jen’s shoes were too long, so she decided to cut them. What type of change happened to her shoelaces?

Answer 10

Physical change

Question 11

If you mix together flour, butter, chocolate chips, and a little baking soda, and shape it into flat circles, what kind of change have you made?

Answer 11

Physical change

Question 12

If you mix together flour, butter, chocolate chips, and a little baking soda, shape it into flat circles, and put it in an oven for about 20 minutes, it turns into something very tasty. What kind of change has happened?

Answer 12

Chemical change

Question 13

If you combine two types of matter and evergy is given off, what type of change is likely to have occured?

Answer 13

Chemical change

Question 14

When you mix vinegar and baking soda, they experience a chemical change. What evidence below would lead you to think that the change is a chemical change?

Answer 14

The solution heats up or cools off

Question 15

True or False

If one or more substances change into new substances, a chemical change occured

Answer 15

True

Question 16

What are called the building blocks of molecules?

Answer 16

Atoms

Question 17

What are called gas, gold, oxygen, and hydrogen?

Answer 17

elements

Question 18

What is called something made up of more than one type of atom?

Answer 18

compound

Question 19

How big is a atom?

Answer 19

10,000 times smaller than the width of a human hair

Question 20

What composes an atom?

Answer 20

Nucleus (center) is made out of neutrons and protons(+), with electrons(-) circling it

Question 21

Which do you think has greater mass, a hydrogen atom or an oxygen atom?

Answer 21

an atom of oxygen

Question 22

What are the three parts of the atoms?

Answer 22

Protons
Neutrons
Electrons

Question 23

True of False

The atoms that make up the element oxygen are exactly the same as the atoms that make up the element hydrogen.

Answer 23

False

Question 24

True of False

Atoms of different elements can combine to form compounds

Answer 24

False

Question 25

When two hydrogen atoms and one oxygen atom join together they form what compound?

Answer 25

Water

Question 26

True of false

The element sodium is made of two kinds of atoms with differnt numbers of protons

Answer 26

false

Question 27

On the periodic table, elements are represented by:

Answer 27

chemical symbols

Question 28

Scientists organize all the known elements into a chart called the :

Answer 28

Periodic table