Chapter 7.2: Matter and Its Changes Flashcards
- explain how physical and chemical changes are different - identify the signs of physical and chemical changes - relate energy and chemical change - understand how physical and chemical changes affect mass
What is the definition of a physical change?
“A change in the size, shape, form, or state of matter that does not change the matter’s identity?”
“A change in the size, shape, form, or state of matter that does not change the matter’s identity?”. Is this the definition for a physical or chemical change?
Physical change.
What is the definition of a chemical change?
“A change in the matter in which substances that make up the matter change into other substances with different chemical and physical properties.”
“A change in the matter in which substances that make up the matter change into other substances with different chemical and physical properties.” Is this the definition for a physical or chemical change?
Chemical change.
Is dissolving a physical or chemical change?
Physical change. Dissolving is when two substances are evenly mixed.
When matter changes state (example is when ice turns to water). Is this a physical or chemical change?
Physical change.
Particles in different states of matter have different amounts of energy, true or false?
True. Particles in solids have little energy and particles in gases have the most.
Can you name three signs of a chemical change?
- Light and heat can be signs during burning.
- Has a new substance formed? When you bake a cake for example.
- Color change or change of state can be signs.
- A new gas is formed you can see or smell.
Is formation of gas a sign of a chemical or physical change?
Chemical change. Example is when you cook food and smell it.
What is a precipitate?
A solid that is made by combining two liquids.
“A solid that is made by combining two liquids”. This is the definition of?
A precipitate.
When a firework explodes it produces bright colors. Is color change a sign of a chemical or physical change?
Chemical change.
For chemical reactions to happen, one type of energy has to turn into a different type. True or false?
True.
Photosynthesis is a chemical reaction because light energy is turned into chemical energy in glucose.
A firework releases thermal, light and sound energy.
Which law states that, “the total mass before a chemical reaction is the same as the total mass after the chemical reaction.”?
The law of conservation of mass.
