Consider the following data on some weak acids and weak bases:

acid Ka Base Kb
name Formula Name Formula
acetic acid HCH3CO2 =1.8 x10^5 Pyridine C5H5N =1.7x 10^9
hydrocyanic acid HCN =4.9 10^10 Aniline C6H5NH2 =4.3x 10^10

Use this data to rank the following solutions in order of increasing pH. In other words, select a '1'next to the solution that will have the lowest pH, a '2' next to the solution that will have the next lowest pH, and so on.

Solution pH

a. 0.1 M NaCl
b. 0.1 M C6H5NH3Cl
c. 0.1 M C5H5NHBr
d. 0.1 M NaCN

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.