#### 12th Standard Chemistry English Medium Free Online Test Volume 2 One Mark Questions 2020

12th Standard

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Chemistry

Time : 00:25:00 Hrs
Total Marks : 25
Answer all the questions
25 x 1 = 25
1. What is the decreasing order of strength of bases
OH, NH2- H - C ≡ C and CH3 - CH2-

(a)

OH->NH2- >H-C≡C >CH3-CH2-

(b)

NH2->OH->CH3-CH2- >H-C≡C

(c)

CH3-CH2->NH2->H-C≡C->OH-

(d)

OH->H-C ≡ C->CH3-CH2- >NH2-

2. With regard to the strength of acids and bases, Find the incorrect statement among the following.

(a)

Strong acid is one that completely dissociates in water

(b)

Ka is the dissociation constant

(c)

CH3COOH is a weak acid

(d)

Smaller the Ka value, greater is the acid strength

3. A current strength of 3.86 A was passed through molten Calcium oxide for 41minutes and 40 seconds. The mass of Calcium in grams deposited at the cathode is (atomic mass of Ca is 40g / mol and 1F = 96500C).

(a)

4

(b)

2

(c)

8

(d)

6

4. Which of the statements about electrolytic conductance is not true?

(a)

Conductivity increases with decrease in viscosity.

(b)

Higher dielectric constant shows lower conductance in solution.

(c)

Temperature increases, conductance also increases.

(d)

Molar conductance increases with increase in dilution.

5. The most effective electrolyte for the coagulation of AS2S3Sol is ____________

(a)

NaCl

(b)

Ba(NO3)2

(c)

K3[Fe(CN)6]

(d)

Al3+

6. Pick the odd one out.

(a)

dialysis

(b)

electro dialysis

(c)

electrophoresis

(d)

ultrafiltration

7. Tyndall effect is a _____property of colloidal particles.

(a)

optical

(b)

kinetic

(c)

electrical

(d)

eletromc

8. (CH3)3-C-CH(OH) CH3 $\overset { con{ H }_{ 2 }{ SO }_{ 4 } }{ \longrightarrow }$X (major product) ___________

(a)

(CH3)3 CCH = CH2

(b)

(CH3)2C = C (CH3)2

(c)

CH2= C(CH3)CH2-CH2- CH3

(d)

CH2= C (CH3) - CH2- CH2- CH3

9. Among the following ethers which one will produce methyl alcohol on treatment with hot HI?

(a)

(H3C)-3C-|-O-CH3

(b)

(CH3-)2-CH-CH2-O-CH3

(c)

CH3-(CH2)3-O-CH3

(d)

CH3-CH2-$\underset { \overset { | }{ { CH }_{ 3 } } }{ CH }$-O-CH3

10. Which one of the following would not react with cone. HCI and anhy. ZnCl2 at room temperature?

(a)

(CH3)3COH

(b)

(CH3)2CHOH

(c)

${ CH }_{ 3 }-{ CH }_{ 2 }-\underset { \overset { | }{ { CH }_{ 3 } } }{ CH } -OH$

(d)

CH3CH2CH2OH

11.  is __________

(a)

Mesitylene

(b)

Pyrogallol

(c)

Hydroxy quinol

(d)

Phluroglucinol

12. Assertion: 2,2 – dimethyl propanoic acid does not give HVZ reaction.
Reason: 2 – 2, dimethyl propanoic acid does not have $\alpha$ - hydrogen atom
Codes:
(A) if both assertion and reason are true and reason is the correct explanation of assertion.
(B) if both assertion and reason are true but reason is not the correct explanation of assertion.
(C) assertion is true but reason is false
(D) both assertion and reason are false

(a)

if both assertion and reason are true and reason is the correct explanation of assertion.

(b)

if both assertion and reason are true but reason is not the correct explanation of assertion.

(c)

assertion is true but reason is false

(d)

both assertion and reason are false

13. Assertion: p – N, N – dimethyl amino benzaldehyde undergoes benzoin condensation
Reason: The aldehydic (-CHO) group is meta directing.
Codes:
(A) if both assertion and reason are true and reason is the correct explanation of assertion.
(B) if both assertion and reason are true but reason is not the correct explanation of assertion.
(C) assertion is true but reason is false
(D) both assertion and reason are false

(a)

if both assertion and reason are true and reason is the correct explanation of assertion.

(b)

if both assertion and reason are true but reason is not the correct explanation of assertion.

(c)

assertion is true but reason is false

(d)

both assertion and reason are false

14. Which among the carbonyl compounds cannot be prepared by Rosenmund reduction?

(a)

Ketones

(b)

Formaldehyde

(c)

Acetaldehyde

(d)

Both (a) and (b)

15. When aqueous solution of formaldehyde is evaporated to dryness it forms a polymer called

(a)

paraldehyde

(b)

paraformaldehyde

(c)

bakelite

(d)

polyamide

16. Nitration of nitrobenzene results in

(a)

o-dinitrobenzene

(b)

1,3,5 trinitrobenzene

(c)

m-dinitrobenzene

(d)

p-dinitrobenzene

17. Nitromethane condenses with acetaldehyde to give

(a)

nitro propane

(b)

1-nitro-2-propanol

(c)

2-nitro-1-propanol

(d)

3-nitro propanol

18. The reagent that cannot be used for the conversion of C6H5NO2 ➝ C6H5NH2

(a)

Sn/HCI

(b)

LiAlH4

(c)

H2/Ni

(d)

Zn/NaOH

19. The intermediate formed in the nitration of benzene is _________

(a)

Arenium ion

(b)

Carbanion

(c)

Oxonium ion

(d)

Nitrite ion

20. In a protein, various amino acids linked together by __________

(a)

Peptide bond

(b)

Dative bond

(c)

$\alpha$-Glycosidic bond

(d)

$\beta$ - Glycosidic bond

21. A dipeptide does not have

(a)

two peptide units

(b)

portions of two amino acids

(c)

an amino group

(d)

salt like structure

22. Proteins are found to have two different type of secondary structures, a-helix and P pleated sheet structure a-helix structure of protein is stabilised by_________

(a)

peptide bond

(b)

vander Waalsforces

(c)

hydrogenbonds

(d)

dipole - dipole interaction

23. Pick out the wrong statement among the following.

(a)

Antipyretics is used to reduce the body temperature

(b)

Analgesics are drugs used to relieve pain

(c)

Milk of magnesia is used to relieve symptoms of heat burn

(d)

Tetracyclines are antifertility drugs

24. Addition polymerisation is also called as _______ polymerisation.

(a)

chain growth

(b)

condensation

(c)

step growth

(d)

none of the above

25. Which is not an artificial sweetener is ______

(a)

Dulcin

(b)

Nectarin

(c)

Sucralose

(d)

Sodium benzoate