Mass percent mass of chemicaltotal mass of compound x 100. Subtract 100 from that. Percentage Change D V V 1 100.
The formula for calculating change is new value old value old value.
You must multiply by 100 at the end to express the value as a percentage. Take 10 percent and divide by 2nd percentage. Next subtract the old value from the new value. To determine the percent change in an objects mass you first need to know how much.