Which of the following best describes the difference between a mixture and a pure substance? A. A mixture has the same properties throughout; a pure substance has the different properties throughout. B. A mixture has different properties throughout; a pure substance has the same properties throughout A mixture is made up of only one type of atom; a pure substance is made up of more than C. one type of atom. A mixture is made up of more than one type of atom; a pure substance is made up of only D. one type of atom.

B. A mixture has different properties throughout; a pure substance has the same properties throughout

Explanation:

We have two classes of substances which are pure and impure substances.

Pure substances are elements and compounds

Impure substance are simply mixtures.

Mixtures have the following properties;

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

on passing the small ampere of electric current through the tube made of ar and hg of cfl generates uv rays which excites the fluorescent and thus emits the high radiation by consumption of just 5- 12 w in comparison to incandescent light which requires more power such as around 40 - 55 w to lighten.

moreover the life span of fluorescent or cfl is around 8000 h whereas the life span of incandescent is around 1200 h

hence, the building installed with incandescent lights bears more electricity bill.