The final step for the extraction of copper from copper pyrites in Bessemer converter the reaction involves is as :
1) Cu2S + 2FeO ⟶2Cu + 2Fe + SO2
2) Cu2S + 2CuO ⟶ 6Cu + SO2
3) 4Cu2S + FeS⟶ 8Cu + 2FeSO4
4) 2Cu2O+FeS⟶4Cu+2Fe+SO2
Correct Answer :2
SOLUTION
The final step for the extraction of copper from copper pyrites in Bessemer converter the reaction involves is as Cu2S+2CuO⟶6Cu+SO2
This reaction represents auto reduction. Cu2O reacts with Cu2S to give copper metal. The solid metal obtained is called as blister copper and is about 99% pure.
6. A sample of CaCO3 contains 3.01 x 1023 ions of Ca2+ and CO3 2-. The mass of the sample is (Given atomic mass: Ca = 40, C = 12, O = 16)
1) 50 g
2) 5 g
3) 100 g
4) 200 g
Correct Answer :1
1) Half life of a third reaction is inversely proportional to the square of initial concentration of the
reactant
2) Molecularity of a reaction may be zero or fraction
3)For a first order reaction t1/2 = 0.693/k
4) Rate of zero order reaction is independent of initial connection of reactant.
Correct Answer :2
The pH of the solution produced when an aqueous solution of pH 5 is mixed with an equal volume of an aqueous solution of pH 3 is:
(1) 3.3
(2) 3.5
(3) 4.0
(4) 4.5
Correct Answer :1
The oxidation number of Pt in [Pt(C2H4)Cl3]− is:
1) +1
2) +2
3) +3
4) +4
Correct Answer :2
SOLUTION
[Pt(C2H4)cl3]−
oxidation no. of C2H4=0
oxidation no. of cl=−1
∴x+0+3(−1)=−1
⇒x=+2
⇒⇒ oxidation no. of pt=+2
1)CH2 = CH2
2) C2H5HSO4
3)CH3CHO
4) HCHO
Correct Answer :3
Which of the following biomolecules contain a non-transition metal ion?
(1) Vitamin B12
(2) Haemoglobin
(3) Chlorophyll
(4) Insulin
Correct Answer :3
Benzaldehyde is different from aliphatic aldehydes in its reaction towards
1) NaHSO3 solution
2) Fehling's solution
3) Schiff's reagent
4) Tollens reagent
Correct Answer :2
Which one of these statements are incorrect for pesticides?
1) They are easily bio-degradable
2) They bring toxic effects on humans and animals
3) They decrease the fertility of soil
4) They are quite stable
Correct Answer :1
Pesticides not only bring toxic effect on human and animals but also decrease the fertility of the soil. Some of the pesticides are quite stable and their bio- degradation may take weeks and even months.
The adsorption of a gas, on a solid surface, varies with pressure of the gas in which of the following manner?
1) Slow fast independent of the pressure
2) Fast slow independent of the pressure
3) Independent of the pressure slow fast
4) Independent of the pressure fast slow
Correct Answer :2
The adsorption of a gas on the solid surface varies in the following manner.
Fast ⟶ Slow ⟶independent of pressure.