Apositron is a particle similar to an electron, but with the opposite charge of an electron. if a positron and an electron collide, sometimes both the electron and positron disappear, and two photons are created. this is an example of

Annihilation of matter

Explanation:

Matter is annihilated when it collides with its antiparticle leading to a tremendous release of energy. This contradicts the law of conservation of matter which states that matter can neither be created nor destroyed.

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o