Science Unit 6 Flashcards
What is the difference between physical and chemical changes?
A physical change may vary the material in shape or size and it can typically be undone, but in a chemical change it will change color and the substance itself.
What are examples of physical changes?
Cutting paper
Ice melting
Smashing a lightbulb
Folding paper
What are some examples of chemical changes?
Wood burning to ash
Food digestion
Combustion
Metal rusting
Banana turning brown
What is a chemical property?
A chemical process is wether a substance can change into another, or not. They can also be identified with
Flammability
Reactivity
What is a physical property?
Physical properties can be observed. They can also be identified with
Density
Melting and boiling point
Color
Texture
Odor
Solubility
Malleability
Conductivity
What is thermal energy?
Kinetic energy of particles of matter
Energy flow examples
Hot pan straight out of the oven
Person throwing a basketball
Types of thermal energy transfer
Conduction, convection and radiation
What is conduction?
When thermal energy is transferred between particles by direct contact. When the particles heat up, they go faster and bump into each other that sends energy through where it is.
What is convection?
Thermal energy is transferred throughout liquids and gases. When the air warms up, the air particles move faster and become less dense. The more dense, cold particles drop.
What is radiation?
Thermal energy is transferred through electromagnetic waves. The radiation travels through empty space until it hits a particle, the particle absorbs the radiation and converts it into thermal energy.
What endothermic reactions?
Thermal energy is absorbed. The reaction is cooler than its surroundings. Temperature decreases
What are exothermic reactions?
Thermal energy is released. The reaction is hotter than the surroundings. Temperature increases.
