Notes 3-1

Question 1

Law of Conservation of Mass

Answer 1

Mass is neither created nor destroyed during ordinary chemical and physical changes

Question 2

Law of definite proportions

Answer 2

Chemical compounds contain the same elements in exactly the same proportions by mass regardless of the sample size
(ex. a drop of water has the same chemical proportions as a bucket of water)

Question 3

Percent by mass

Answer 3

percent by mass = mass of element/mass of compound x 100