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
