Topic 2 Lesson 3: Chemical Changes

Question 1

Lesson 3. A process in which a new kind of matter forms

Answer 1

chemical change

Question 2

The scientific law that in any physical change or chemical change, the total mass of the matter does not change

Answer 2

Conservation of Matter

Question 3

The process in which one or more substances change into one or more different substances.

Answer 3

Chemical Reaction

Question 4

A chemical change is a change that produces one or more new _______________.

Answer 4

substances

Question 5

Example: When charcoal burns, a chemical change occurs in which charcoal and oxygen form new __________________. These new ________________ are ashes and gases that you cannot see.

Answer 5

substances

Question 6

When a chemical change occurs, the _______________ that make up the original substances rearrange to form new substances.

Answer 6

particles

Question 7

___________ of a chemical change may include the release of heat or light, a change in color, a new smell, gas bubbles, or the formation of a solid.

Answer 7

Evidence

Question 8

After a chemical change happens, the same particles are in the two new substances, but they are ________________ differently.

Answer 8

arranged

Question 9

The law of Conservation of Matter states that in any chemical change or physical change, the total ______________ of the matter does not change.

Answer 9

mass

Question 10

In a chemical change, all the particles that make up the original ______________ end up in the new _______________.

Answer 10

substance

Question 11

The combined ______ of the substances before a chemical change is the same as the combined ________ of the substances after the chemical change.

Answer 11

mass

Question 12

When you observe one or more substances change into one or more new substances, you observe a chemical ___________.

Answer 12

reaction

Question 13

Example: Nails rust as a result of a __________ ________. The iron in the nails and oxygen gas from the air react to form _____.

Answer 13

chemical reaction; rust

Question 14

Chemical changes occur in the ________ all the time.

Answer 14

kitchen

Question 15

Example: A __________ _______ occurs when a chef makes fresh cheese. To make fresh cheese, the chef adds lemon juice to whole milk. Once the two liquid ingredients are mixed, _______ pieces start to form. The solid pieces, called ______, are chunks of the fresh cheese. They form as a result of a chemical change. To prepare the cheese to eat, the chef __________ the curd from the liquid.

Answer 15

chemical change; solid; curds; separates

Question 16

Lesson 4. A substance where different materials are put together but each keeps its own properties.

Answer 16

mixture

Question 17

A mixture in which the substances are evenly spread out and do not settle to the bottom of the container.

Answer 17

solution

Question 18

In a mixture, different materials are placed together, but each material in the mixture keeps its own ___________.

Answer 18

properties

Question 19

Example: If you mix peanuts and raisins, each of the _____________ keeps its own properties. You can easily separate the peanuts from the raisins.

Answer 19

substances

Question 20

A solution is a mixture in which substances are spread out ________________ and do not settle to the bottom of the container.

Answer 20

evenly

Question 21

Example: If you place salt in water, the salt and water form a __________. The salt seems to “disappear”, so the salt water is a _____________.

Answer 21

mixture; solution

Question 22

The substance that is dissolved in the solution is called the ___________.

Answer 22

solute

Question 23

The substance in which the solute is being dissolved is called the _________.

Answer 23

solvent

Question 24

The components of a solution keep their own ___________________, but they usually cannot be separated as easily as other mixtures. This is because the components of a solution are evenly ______.

Answer 24

properties; mixed

Question 25

All solutions are ____________, but not all ____________ are solutions.

Answer 25

mixtures

Question 26

Example: Clear apple juice is a solution. Any samples of the juice are just ________, and there are no separate particles in the mixture.

Answer 26

alike

Question 27

Example: Fresh squeezed orange juice is not a ___________. You can see __________ of orange in the mixture.

Answer 27

solution; chunks