Changes in Matter
What kind of change does not form a new substance?
A physical change
What is the process called when a liquid changes into a solid
Freezing
What is formed when two or more substances are physically combined without making a new substance?
In saltwater, what is the substance being dissolved called?
Solute (salt)
Name one sign that a chemical change may have happened
A change in color, odor, or state of matter
What type of change happens when iron rusts?
A chemical change
What is the process called when a gas changes into a liquid
Condensation
What type of mixture is vegetable soup?
Heterogenous Mixture
In saltwater, what is the substance doing the dissolved called?
Solvent (water)
What is a solid solution containing two or more elements, including a metal, called?
Alloy
What is a change that forms a new substance called?
A chemical change
When ice cream melts, what special temperature has it reached?
Melting point
What is a mixture called when its substances are spread evenly throughout?
Homogenous Mixture
What do we call a homogenous mixture in which substances are spread evenly throughout?
Why must a pastry chef use the correct baking temperature and time?
Because chemical changes occur during baking, and the proper temperature and time help ensure the pastry cooks correctly
What does the law of conservation of matter say?
Matter cannot be created or destroyed; it can only change
What temperature has melted candle wax reached when it begins to solidify
Freezing point
How could you separate small metal pieces from a mixture of rice and metal?
Magnetic attraction
What is a saturated solution?
A solution holding all the solute its solvent can dissolve
A carton of milk smells unpleasant. What should you do, and what might the odor indicate?
Do not serve the milk. Unpleasant odor may indicate a chemical change and spoilage
When a log burns, why is the mass of the ashes less than the original?
Some of the matter becomes gases and released into the air
A cold window causes water vapor in the air to form liquid droplets. What process is happening, and why?
Condensation. The gas could and changes into liquid
Explain the difference between a homogenous and heterogenous mixture. Give an example of each.
A homogenous mixture is uniform throughout (salt water). A heterogenous mixture is not uniform (vegetable soup).
Name three ways to make a solid dissolve faster in a liquid
Crush or break it into smaller pieces, stir the mixture, and the heat the solvent
How does the law of conservation of matter connect with the Bible's teaching about creation?
The law says matter cannot be created or destroyed through ordinary changes. The Bible teaches that God create matter and holds creation together. People can change matter but cannot create it out of nothing