Accuracy vs Precision:

Accuracy: how close your results are to the accepted value.

Precision: how close your data are to each other.

Errors: systemic and random

Percent error: |(accepted value-experimental value)/(accepted value)x(100)|

Experimental value= average of trials

Accepted value= given.

Density:

Density= mass/volume

The amount of the substance does not affect the density because the mass and volume will increase in a ratio together (ex, as the mass increases the volume increases the same amount)