Topic 2 Lesson 3: Chemical Changes Flashcards
(27 cards)
Lesson 3. A process in which a new kind of matter forms
chemical change
The scientific law that in any physical change or chemical change, the total mass of the matter does not change
Conservation of Matter
The process in which one or more substances change into one or more different substances.
Chemical Reaction
A chemical change is a change that produces one or more new _______________.
substances
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.
substances
When a chemical change occurs, the _______________ that make up the original substances rearrange to form new substances.
particles
___________ 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.
Evidence
After a chemical change happens, the same particles are in the two new substances, but they are ________________ differently.
arranged
The law of Conservation of Matter states that in any chemical change or physical change, the total ______________ of the matter does not change.
mass
In a chemical change, all the particles that make up the original ______________ end up in the new _______________.
substance
The combined ______ of the substances before a chemical change is the same as the combined ________ of the substances after the chemical change.
mass
When you observe one or more substances change into one or more new substances, you observe a chemical ___________.
reaction
Example: Nails rust as a result of a __________ ________. The iron in the nails and oxygen gas from the air react to form _____.
chemical reaction; rust
Chemical changes occur in the ________ all the time.
kitchen
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.
chemical change; solid; curds; separates
Lesson 4. A substance where different materials are put together but each keeps its own properties.
mixture
A mixture in which the substances are evenly spread out and do not settle to the bottom of the container.
solution
In a mixture, different materials are placed together, but each material in the mixture keeps its own ___________.
properties
Example: If you mix peanuts and raisins, each of the _____________ keeps its own properties. You can easily separate the peanuts from the raisins.
substances
A solution is a mixture in which substances are spread out ________________ and do not settle to the bottom of the container.
evenly
Example: If you place salt in water, the salt and water form a __________. The salt seems to “disappear”, so the salt water is a _____________.
mixture; solution
The substance that is dissolved in the solution is called the ___________.
solute
The substance in which the solute is being dissolved is called the _________.
solvent
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 ______.
properties; mixed
