. Write down the molecular weight of the following compounds. 1. Ammonium nitrate
NH4 NO3
= 1 X14 + (4x1)+ 1 X 14 +(3x16) = 14 + 4 + 14 +48
= 80 amu.
2. Ammonium Chloride NH4 Cl
3. Ammonium Hydroxide NH4 OH
4. Aluminium hydroxide Al (OH)3
5. Calcium oxide Ca O
6. Calcium Chloride Ca Cl2
7. Calcium bicarbonate Ca( HCO3)2
8. Magnesium Oxide Mg O
9. Magnesium Sulphate Mg SO4
10. Potassium hydroxide K OH
11. Sodium Nitrate Na NO3
12. Sodium carbonate Na2 CO3

Q2. Choose the correct option:

1)A plastic that can be heated and remolded

a) Polythene

b) Thermosetting plastic

c) Thermoplastic

d) Polyester

2)Which of the following is a cash crop:

a) Pepper

b) Cereals

c) Banana

d) Pulses

3)is caused by a bacteria :

a) Common cold

b) Chicken pox

c) Ringworm

d) Tuberculosis

4)Ais a modern tool used to plough the land.

a) Cultivator

b) Harvester

c) A plough

d) Khurpi

5)The first antibiotic discovered was:

a) Staphylococcus

b) Streptomycin

c) Penicillin

d) Tetracycline

6)The fabric used for making bags should be:

a) Light

b)water

c) Have high tensile strength

d)All of the above

i dont know

explanation:

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.