a few MCQs

[Jessieee]

1. the formation of chemical bonds in molecules will result in

a. the attraction between electrons

b. the liberation of heat

c. the attraction between nucei

d. even distribution of electrons

ans is b, but i wanna ask will it result in the attraction between anything, even not between neither the nuclei nor the electrons

 

 

2. which of the following statments abt redox reaction is false

a. some common oxidizing agent can also be reducing agents in other reactions

b. oxidation n reduction take place at the same time

c. redox reactions involve electron transfer

d. a current can be detected

ans is d, i know why d is false, but i think a is not reli correct either...

 

3. hot conc sulphuric acid reacts with sodium chloride to form HCl gas. in this reaction, conc sulphuric acid acts as

a. a strong acid

b. an oxidizing agent

c. a dehydrating agent

d. a dibasic acid

ans is a...is it only becoz it is a strong acid?

 

4. during the preparation of a greasy chinese dish, some peanut oil was stongly heated in a metal wok. it was found that the fumes didnt condense back to liquid on cooling. the formation of such fumes may be explained by the fact that

a. combustion converted the oil molecules to CO2 n water

b. oil molecules were converted to a polymer

c. oil molecules were fragmented into smaller pieces

d. oil was hydrolsed into acids n glycerol

ans is c...no idea

 

5. which of the following statments abt the compound, CH3CH2COOH, is incorrect?

a. it can undergo polymerisation

b. it has a sour taste

c. it can be made from ethanol

d. it is a food preservatives

ans is a, but i think it can undergo polymerisation

 

6. lather formed by detergent n water

(1) kills fish in water

(2) holds suspended dirt n grease in water

(3) block the traffic in waterways

which is/are true?

a. 1 and 2

b. 1 n 3

c. 2 n 3

d. 1, 2 n3

ans is b, actually what is the lather? how is it form?

 

7. which of the following can undergo polymerisation

(1) ....

(2) NH2-CH2-CH2-CH2-CH2-CH2-COOH

(3) NH2-CH2-CH2-CH2-CH2-CH2-OH

y cant (3) undergo polymerisation?

 

thats all...thx!

[wolfson]

ethanol + propionic acid => ethyl propionate

 

&

 

Propionic acid does not undergo polyaddition/ploymerisation, however with its anhydride on purified cellulose, it forms the basis of a thermoplastic moulding material.