EXAM Flashcards
electrons
negative
neutrons
neutral (no charge)
how do you calculate the number of neutrons
atomic mass (rounded) - atomic number
what is the central area of an atom called
the nucleus
what is the law on conservation of matter
matter can never be destroyed or created but it can be changed
physical change definition
a chnage where the matter looks different but is still made of the same substance or chemical
chemical change definition
a chnage where a new substance is formed
how can you know it’s a chemical chnage
- a new solid has formed
- a new gas has formed
- a new colour is visible that doesn’t go away
- a change im temperature
- a pH change
what is a chemical reaction
when you mix two or more chemicals and get new chemicals
what are the chemicals you mix called
reactants
what are the new chemicals you make called
products
solid to liquid
melting
gas to liquid
condensation
solid to gas
sublimation
liquid to solid
solidification