Matter, Models and Density Flashcards
What is matter made of?
Atoms
How are atoms sometimes pictures as?
A small ball
What is it called when alpha particles fired at atoms bounce back?
Alpha scattering
What is the difference between the mass of the nucleus and the electrons in an atom?
The nucleus contains almost all the mass
What can electric charges cause in between atoms?
Forces
Some atoms can form groups held together by electric force. What are these groups called?
Molecules
What is the density of gases?
Low
What is the density of liquids?
Medium
What is the density of solids?
High
What is density?
Mass per unit volume
Ratio of mass to volume
How do you find the density of an irregularly shaped object?
You need to find the volume - fill a eureka can with water -weigh the object - put the object in the eureka can -measure volume of water displaced Fill in formula
Gas to solid
Deposition
Solid to gas
Sublimation
Gas to liquid
Condensation
Liquid to gas
Evaporating
Liquid to solid
Freezing
Solid to liquid
Melting
If 100g of water is frozen, how many grams of ice will there be and why?
100g
-conservation of mass
What is a physical change?
A reversible change
Their original properties can be recovered
What is a chemical change?
An irreversible change
Their properties are permanently changed
Give an example of a chemical change
Lighting a match
Frying an egg
Baking a cake
Give an example of a physical change
Freezing water
Melting chocolate
Mixing flour and sugar