Applied Science 2018 (Even) | SBTE Bihar

Chemistry

Group A

1. Choose the most suitable answer from the following options.  (1×10)

11). Siderite is an ore of :

(a) Ag
(b) Al
(c) Cu
(d) Fe

12). Teflon is a polymer of 

(a) Acetates
(b) Propenes
(c) Alkenes containing fluorine
(d) Fluoro Propenes.

13). Which of the following is primary cell :

(a) Nickel - Cadmium cell
(b) Mercury cells
(c) Lead storage cell
(d) None of these

14). In electro - refining the impure metal is made 

(a) Anode
(b) Cathode
(c) Both (a) and (b)
(d) None of these

15). Acid value of good lubricant should be :

(a) High
(b) Least
(c) Moderate
(d) None of these

16). Ferric oxide in blast furnace is reduced by :

(a) Co2
(b) CO
(c) C
(d) None of these

19). Which of the following does not occur in nature ?

(a) Cotton
(b) Nylon
(c) Wool
(d) Silk

20). Most commonly used safety fuse wire is made of 

(a) Lead
(b) Nickel
(c) Tin
(d) An alloy of tin and lead.

Group B

Answer all Three Questions.   (3×4)

2. What is the difference between potential difference and electromotive force ? 

Or

Describe the manufacture of steel by Bessemer process.

3. A solution of CuSo4 is electrolysed for 10 minutes with a current of 1.5 amperes. What is the mass of copper deposited at the cathode ?

Or

What are characteristics of good Lubricants ?

4. Explain the construction and working of Lead Storage battery.

5. How is steels are classified on the basis of percentage of carbon ? Write two properties and two applications of each of them.

6. Define alloys and purpose of making alloys ?

7. Explain four factors in brief which affects the rate of electrochemical corrosion.