Question

Marks :-15
I. Choose the correct answer. 10x1=10
1. When a mixture of aluminium powder and iron oxide is ignited -----is reduced to metal.
a) aluminium b) Iron
c) aluminium oxide d) iron oxide
2. The valency of copper when It forms copper ll oxide on heating at 1370k is
MWIMWI
a) +1b) +2 c) +3 d)-2
3.Limestone decomposing to calcium oxide and carbondioxide is an example of----- reaction as there is---
a) exothermic , absorption of heat
b) endothermic, liberation of heat
c) endothermia, absorption of heat
d) exothermic, liberation of heat
4. The percentage of carbon in steel is ------ and pigiron is
WIMMINI
a) <0.25% 0.25-2%
b) 2-4.5% <0.25
c) >0.25% 0.25-2%
d) <0.25% 2-4.5%​

Answer 1

ye to kam se kam 20 marks ke liye hona chahiye