Test 4/19 Flashcards
A change from one substance to another
Chemical change
To make new substances from compounds by rearranging the atoms
Chemical reaction
2NaCl -> 2Na + Cl
2
Chemical equation
The starting material in a chemical reaction and is placed on the left side
Reactants
Material in a chemical reaction and is placed on the right side
Product
What does the law of conservation of mass state?
The total mass before a chemical reaction is equal to the total mass after the reaction
A measure of how tightly the particles are packed together in a given volume
Density
Why do we use density to identify an unknown object?
Everything has a different, unique density, and density does not change unless there is a large temperature change
How do you find density?
2 ways
Mass divided by volume
3 1g/cm
How do you find mass?
Density•Volume
How do you find volume?
Mass divided by density
A change in a substance that does not change the identity of a substance
Physical Change
Name a rule for sinking
An item will sink if the density is greater than the density of that liquid
Name a rule for floating
And item will float in a liquid if its density is less than the density of the liquid
Which density will be at the bottom?
Largest
Which density will be on top?
Lowest
What will form layers in a container by their densities?
Liquids
