Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

Carbon cannot be used in the reduction of Al_2 O_3 because

Answer»

it is an EXPENSIVE PROPOSITION
the ENTHALPY of FORMATION of `CO_2` is more than that of` Al_2 O_3`
pure carbon is not easily available
the enthalpy of formation of `Al_2 O_3`

Answer :D
2.

Carbon can reduce ferric oxide to iron at a temperature above 983 K because

Answer»

carbon monoxide formed is thermodynamically less satble than ferric oxide
carbon has a HIGHER affinity TOWARDS oxidation than iron.
free energy change for the formation of carbon dioxide is less NEGATIVE than that for ferric oxide.
iron has a higher affinity towards oxygen than carbon.

Answer :B
3.

Carbon burns in air and forms two oxides CO and CO_2.This shows that carbon has :

Answer»

Two ALLOTROPIC forms
Two oxidation states
Two isotopes
4 ELECTRONS in VALENCE shell

Answer :B
4.

Carbon black, which is used in making printer's ink is obtained by the decomposition of

Answer»

Acetylene
Carbon-tetrachloride
Benzene
Methane

Answer :D
5.

Carbon black, which is used in making printer's ink, is obtained by decomposition of

Answer»

Acetylene
Benzene
Carbon tetrachloride
Methane

Solution :`CH_4+O_2underset"Limited supply of air"oversetDeltatoC+2H_2O`
It CONTAINS 98-99% carbon. It is USED in MAKING black ink, PAINTS and shoe polishes
6.

Carbonblackis obtained whenmethaneis :

Answer»

heatedin absenceof air
Heated in PRESENCEOF NITROGEN
heatedin presenceofammonia
heatedwithsteam

ANSWER :A
7.

Carbon atoms in the compound (CN)_(4)C_(2) are

Answer»

SP HYBRIDIZED
`sp^(2)` hybridized
sp & `sp^(2)` hybridized
sp, `sp^(2)` & `sp^(3)` hybridized

Solution :
8.

Carbon atoms in fullerene with formula C_(60) have

Answer»

`SP^(3)` hybridised
sp hybridised
`sp^(2)` hybridised
partially `sp^(2)` and partially `sp^(3)` hybridised

Answer :B::C::D
9.

Carbon atoms in diamond are bonded with each other in configuration :

Answer»

planer
linear
octahedral
tetrahedral

Answer :D
10.

Carbon atoms in fullerence with formula C_(60) have………

Answer»

`SP^(3)` hybridised
sp hybridised
`sp^(2)` hybridised
partialy `sp^(2)` and PARTIALLY `sp^(3)` hybridised

Answer :C
11.

Carbon atoms in diamond are bonded to each other in configuration which is :

Answer»

Planar
Linear
Tetrahedral
Octahedral

Answer :C
12.

Carbon atoms bearing the -OH group in phenols and CH_(2)=CH-OH are

Answer»

both hybridised `SP^(2)`
both hybridised `sp^(3)`
`sp^(2) and sp^(3)` hybridised RESPECTIVELY.
`sp^(3) and sp^(@)` hybridised respectively.

ANSWER :A
13.

Carbon atom of carbonyl gp. In aldehyde is of :

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`1^@`
`2^@`
`3^@`
None

Answer :A
14.

Carbon atom of carbonyl group In a ketone is of :

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`1^@`
`2^@`
`3^@`
None

Answer :B
15.

Carbon atom of carbonyl group In aldehyde is of :

Answer»

`1^@`
`2^@`
`3^@`
None

Answer :A
16.

Carbon atom in methyl carbocation contains how many pairs of electrons?

Answer»

8
4
3
5

Answer :C
17.

Carbon atom in carboxyl group is

Answer»

SP-hybridised state
`sp^(2)` - hybridised state
`sp^(3)` - hybridised state
`sp^(3)` -d- hybridised state

Answer :B
18.

Carbon atom holding halogen in aryl halides is:

Answer»

`sp^2-Hybridized`
`sp^3-Hybridized`
`sp-Hybridized`
`sp^3d-Hybridized`

ANSWER :A
19.

Carbon atom holding halogen in aryl halides is :

Answer»

`SP^(2)` HYBRIDIZED
`sp^(3)` hybridized
sp-hybridized
`sp^(3)` d-hybridized

Answer :A
20.

Carbon and oxygen forms two compound . Carbon content in one of them is 42.9% while in the other is 27.3% . Thegiven data is in support with

Answer»

LAW of definite proportions
law of RECIPROCAL proportions
law of MULTIPLE proportions
law of CONSERVATION of mass

Answer :C
21.

Carbon and hydrogen are estimated by :

Answer»

Liebig's METHOD
Carius method
Duma's method
NONE of the above

Answer :A
22.

Carbon and CO gas are used to reduce which of the following pairs of metal oxides for extraction of metals?

Answer»

`FEO, SNO`
`SnO, ZNO `
`BAO, Na_2 O_2`
`FeO,ZnO `

SOLUTION :`FeO,ZnO `
23.

Carbon and CO gas are used to reduce which of the following pairs of metal oxides for extraction of metals ?

Answer»

FEO, SnO
SnO, ZNO
`BAO, Na_(2)O_(2)`
`FeO_(4)ZnO`

Solution :
24.

Carbon and carbon monoxide burn in oxygen to form carbon dioxide according to the following reactionsC+O_(2)rarrCO_(2), DeltaH=-394 " kJ mol"^(-1)2CO+O_(2)rarr2CO_(2),DeltaH=-569 " kJ mol"^(-1)The heat of formation of 1 mol of carbon monoxide is thus

Answer»

`-219.0 kJ mol^(-1)`
`-109.5 kJ mol^(-1)`
`-175.0 kJ mol^(-1)`
`-87.5 kJ mol^(-1)`

Solution :`C+O_(2)rarrCO_(2)+394 kJ "….(i)"`
`2C+2O_(2)rarr2CO_(2)+788 kJ "….(ii)"`
`2CO_(2)+O_(2)rarr2CO_(2)+569 kJ "….(iii)"`
`2CO_(2)rarr2CO+O_(2)-569 kJ "….(IV)"`
EQ. (ii) +eq. (iv) = - 109.5 kJ`mol^(-1)`.
25.

Carbon-14 used to determine the age of organic material. The procedure is absed on the formation of C^(14) byneutron capture iin the upper atmosphere. ._(7)N^(14)+._(0)n^(1) rarr ._(6)C^(14)+._(1)H^(1) C^(14) is absorbed by living organisms during photosynthesis. The C^(14) content is constant in living organism. Once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of C^(14) in the dead being falls due to the decay, which C^(14) undergoes. ._(6)C^(14)rarr ._(7)N^(14)+beta^(c-) The half- life period of C^(14) is 5770 year. The decay constant (lambda) can be calculated by using the following formuls : lambda=(0.693)/(t_(1//2)) The comparison of the beta^(c-) activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle. The method, however, ceases to be accurate over periods longer than 30000 years. The proportion of C^(14) to C^(12) in living matter is 1:10^(12). A nuclear explosion has taken place leading to an increase in the concentration of C^(14) in nearby areas. C^(14) concentration is C_(1) in nearby areas and C_(2) in areas far away. If the age of the fossil is determined to be T_(1) and T_(2) at the places , respectively, then

Answer»

The age of the fossil will increase at the place where explosion has taken place and`T_(1)-T_(2)=(1)/(lambda)ln ``(C_(1))/(C_(2))`
The age of the fossil will decrease at the place where explosion has taken place and`T_(1)-T_(2)=(1)/(lambda)ln``(C_(1))/(C_(2))`
The age of fossile will be DETERMINED to be same.
`(T_(1))/(T_(2))=(C_(1))/(C_(2))`

Solution :All radioactive decays are examples of first`-` order KINETICS.
So decay constant`lambda=(1)/(T_(1)-T_(2))ln``(C_(1))/(C_(2))`
`C_(1)` is the concentration at `T_(1)` time.
`C_(2)` is the concentration at `T_(2)` time.
So, `T_(1)-T_(2)=(1)/(lambda)ln ``(C_(1))/(C_(2))`
26.

Carbon-14 used to determine the age of organic material. The procedure is absed on the formation of C^(14) byneutron capture iin the upper atmosphere. ._(7)N^(14)+._(0)n^(1) rarr ._(6)C^(14)+._(1)H^(1) C^(14) is absorbed by living organisms during photosynthesis. The C^(14) content is constant in living organism. Once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of C^(14) in the dead being falls due to the decay, which C^(14) undergoes. ._(6)C^(14)rarr ._(7)N^(14)+beta^(c-) The half- life period of C^(14) is 5770 year. The decay constant (lambda) can be calculated by using the following formuls : lambda=(0.693)/(t_(1//2)) The comparison of the beta^(c-) activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle. The method, however, ceases to be accurate over periods longer than 30000 years. The proportion of C^(14) to C^(12) in living matter is 1:10^(12). What should be the age of fossil for meaningful determination of its age ?

Answer»

6 years
6000 years
60000years
It can be used to CALCULATE any age

Solution :Radiacarbon DATING method ceases to be accurate over PERIODS longer than 30000 years.
27.

Carbon-14 used to determine the age of organic material. The procedure is absed on the formation of C^(14) byneutron capture iin the upper atmosphere. ._(7)N^(14)+ ._(0)n^(1) rarr ._(6)C^(14)+._(1)H^(1) C^(14) is absorbed by living organisms during photosynthesis. The C^(14) content is constant in living organism. Once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of C^(14) in the dead being falls due to the decay, which C^(14) undergoes. ._(6)C^(14)rarr._(7)N^(14)+beta^(c-) The half- life period of C^(14) is 5770 year. The decay constant (lambda) can be calculated by using the following formuls : lambda=(0.693)/(t_(1//2)) The comparison of the beta^(c-) activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle. The method, however, ceases to be accurate over periods longer than 30000 years. The proportion of C^(14) to C^(12) in living matter is 1:10^(12). Which of the following options is correct ?

Answer»

In LIVING organisms, circulation of `.^(14)C` from the atmosphere is high, so the carbon content is constant in organism.
Carbond DATING can be used to find out the age of earth CRUST and rocks.
Radioactive ABSORPTION due to cosmic radiation is equal to the rate of radioactive decay. Hence, the carbon content remains constant in living organisms.
Carbon dating cannot be used to determineconcentration of `C^(14)` in dead beings.

SOLUTION :Radioactive absorption due to cosmic radiation is equal to the rate of radiactive decay, hence the carbon content as the ratio of `C^(14)` remains constant in living organism.
28.

Carbon - 14 is used to determine the age of organic material . The procedure is based on the formation of ""^(14) C by neutron capture in the atmosphere . T_(1) - T_(2) = (1)/(lambda) "log" (C_(1))/(C_(2)) ""^(14) C is absorbed by living organisms during photosynthesis . The ""^(14) C content is content is constant in living organism once the plant or animal dies , the uptake of carbon dioxide by it increases and the level of ""^(14) C in the dead being falls due to the decay which C^(14) undergoes . ""_(6)^(14) C to""_(7)^(14) N + beta^(-) (""_(-1)^(0)e) . The half- life period of ""^(14) C is 5770 years . The decay constant (lambda) can be calculated using the formula lambda = (0.693)/(t_(1//2)). The comparison of the b^(-) activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle . the method , however , ceases to be accurate over period longer than 30,000 years . The proportion of ""^(14) C to ""^(12) C in living matter is 1 : 10^(2) A nuclear explosion has taken place leading toincrease in concentration of C^(14) is C_(3) nearby areas and C_(2) in areas far away . If the age of the fossil is determined to be T_(1) and T_(2) at the places respectively then

Answer»

the age of the fossil will INCREASE at the place where explosion has taken place and `T_(1)- T_(2) = (1)/(LAMBDA) "log" (C_(1))/(C_(2))`
the age of the fossil will DECREASES at the place where explosion has taken place and `T_(1) - T_(2) = (1)/(lambda) "log" (C_(1))/(C_(2))`
the age of fossil will be determined to be same
`(T_(1))/(T_(2)) = (C_(1))/(C_(2))`

Solution :`lambda T_(1) = 1_n ((c_(1))/(c_(2))) …… (1) lambda T_(2) = 1_(n) ((c_(2))/(c_(1)))….. (2)`
`lambda (T_(1) - T_(2)) = 1_(n) ((c_1)/(c_1)) - 1_n ((c_2)/(c_1)) , lambda (T_(1) -T_(2)) = 1_(n) ((c_(1))/(c_(2)) xx (c_(1))/(c_(2))) , (T_(1) - T_(2)) = (1)/(lambda) xx 1_n ((c_1)/(c_2))`
29.

Carbon - 14 is used to determine the age of organic material . The procedure is based on the formation of ""^(14) C by neutron capture in the atmosphere . T_(1) - T_(2) = (1)/(lambda) "log" (C_(1))/(C_(2)) ""^(14) C is absorbed by living organisms during photosynthesis . The ""^(14) C content is constant in living organism once the plant or animal dies , the uptake of carbon dioxide by it increases and the level of ""^(14) C in the dead being falls due to the decay which C^(14) undergoes . ""_(6)^(14) C to""_(7)^(14) N + beta^(-) (""_(-1)^(0)e) . The half- life period of ""^(14) C is 5770 years . The decay constant (lambda) can be calculated using the formula lambda = (0.693)/(t_(1//2)). The comparison of the b^(-) activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle . the method , however , ceases to be accurate over period longer than 30,000 years . The proportion of ""^(14) C to ""^(12) C in living matter is 1 : 10^(2) Which of the following options is correct ?

Answer»

In living organisms , circulation of `""^(14) C` from atmosphere is high so the carbon content is constant in organism
Carbon DATING can be USED to find out the age of earth crust of ROCKS
Radioactive material absorption is equal to its rate of decay , hence the carbon content remains constant in living organism.
Carbon dating cannot be used to determine concentration of `""^(14) C` in dead being .

Solution :living organism `((C^(14))/(C^(12)))` is maintained as constant VOLUME .
30.

Carbon-14 is used to determine the age of organic material. The procedure is based on the formation of .^(14)C by neutron capture in the upper atmosphere. ._(7)^(14)N + ._(0)^(1)n rarr ._(6)^(14)C + ._(1)n^(1) .^(14)C is absorbed by living organisms during photosynthesis. The .^(14)C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of .^(14)C in the dead being, falls due to the decay which .^(14)C undergoes. ._(6)^(14)C rarr ._(7)^(14)N + beta^(-) The half-life period of .^(14)C is 5770 years. The decay constant (lamda) can be calculated by using the following formula lamda = (0.693)/(t_(1//2)). The comparison of the beta^(-) activity of the dead matter with that of the carbon still in circulation enable measurement of the period of the isolation of the material from the living cycle. The method however, ceases to be accurate over periods longer than 30,000 years. The proportion of .^(14)C " to " .^(12)C in living matter is 1 : 10^(12).A nuclear explosion has taken place leading to increase in concentration of .^(14)C in nearby areas. C^(14) concentrations is C_(1) in nearby areas and C_(2) in areas far away. If the age of the fossil is determined to be T_(1) and T_(2) at the places respectively then

Answer»

The age of the fossil will increase at the place where EXPLOSION has taken and `T_(1) - T_(2) = (1)/(LAMDA "LN" (C_(1))/(C_(2))`
The age of the fossil will decrease at the place where explosion has taken place and `T_(1) - T_(2) = (1)/(lamda) "ln" (C_(1))/(C_(2))`
The age of fossil will be determined to be same
`(T_(1))/(T_(2)) = (C_(1))/(C_(2))`

SOLUTION :All radioactive decays are the examples of first order kinetics
So decay constant `lamda = (1)/(T_(1) - T_(2)) "ln" (C_(1))/(C_(2))`
`C_(1)` is the concentration at `T_(1)` times
`C_(2)` is the concentration at `T_(2)` time
So `T_(1) - T_(2) = (1)/(lamda) ln (C_(1))/(C_(2))`
31.

Carbon-14 is used to determine the age of organic material. The procedure is based on the formation of .^(14)C by neutron capture in the upper atmosphere. ._(7)^(14)N + ._(0)^(1)n rarr ._(6)^(14)C + ._(1)n^(1) .^(14)C is absorbed by living organisms during photosynthesis. The .^(14)C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of .^(14)C in the dead being, falls due to the decay which .^(14)C undergoes. ._(6)^(14)C rarr ._(7)^(14)N + beta^(-) The half-life period of .^(14)C is 5770 years. The decay constant (lamda) can be calculated by using the following formula lamda = (0.693)/(t_(1//2)). The comparison of the beta^(-) activity of the dead matter with that of the carbon still in circulation enable measurement of the period of the isolation of the material from the living cycle. The method however, ceases to be accurate over periods longer than 30,000 years. The proportion of .^(14)C " to " .^(12)C in living matter is 1 : 10^(12). What should be the age of fossil for meaningful determination of its age

Answer»

6 YEARS
6000 years
60,000 years
It can be used to calculate any age

Solution :RADIO carbon dating method CEASES to be accurate over periods longer than 30,000 years
32.

Carbon-14 is used to determine the age of organic material. The procedure is based on the formation of .^(14)C by neutron capture in the upper atmosphere. ._(7)^(14)N + ._(0)^(1)n rarr ._(6)^(14)C + ._(1)n^(1) .^(14)C is absorbed by living organisms during photosynthesis. The .^(14)C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of .^(14)C in the dead being, falls due to the decay which .^(14)C undergoes. ._(6)^(14)C rarr ._(7)^(14)N + beta^(-) The half-life period of .^(14)C is 5770 years. The decay constant (lamda) can be calculated by using the following formula lamda = (0.693)/(t_(1//2)). The comparison of the beta^(-) activity of the dead matter with that of the carbon still in circulation enable measurement of the period of the isolation of the material from the living cycle. The method however, ceases to be accurate over periods longer than 30,000 years. The proportion of .^(14)C " to " .^(12)C in living matter is 1 : 10^(12). Which of the following option is correct

Answer»

In living organisms, circulation of `.^(14)C` from atmosphere is high so the carbon content is constant in organism
Carbon dating can be used to find out the age of earth crust and rocks
RADIOACTIVE absorption due to COSMIC RADIATION is equal to the rate of radioactive decay, hence the carbon content remains constant in living organisms
Carbon dating can not be used to determine concentration of `.^(14)C` in dead beings.

Solution :Radioactive absorption due to cosmic radiation is equal to the rate of radioactive decay, hence the carbon content as the RATIO of `C^(14) " to " C^(12)` remains constant in living organism.
33.

Carbon -14 is used to determine the age of organic material. The procedure, is based on the formation of .^(14)C by neutron capture in the upper atmosphere. ""_(7)^(14)N+_(0)n^(1) to _(6)^(14)C+_(1)n^(1). .^(14)C is absorbed by living organisms during photosynthesis. The .^(14)C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of .^(14)C in the dead being, falls due to the decay.which C^(14) undergoes ""_(6)^(14)C to _(7)^(14)N+beta^(-) The half life period of ^(14)C is 5770 years. The decay constant (lambda) can be calculated by using the following formula lambda=(0.693)/(t_(1//2)) The comparison of the beta^(-) activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle. The method however, ceases to be accurate over periods longer than 30,000 years. The proportion of .^(14)C to .^(12)C in livingmatter is 1 : 10^(12). What should be the age of fossil for meaningful determination of its age ?

Answer»

`6` years
`6000` years
`60,000` years
It can be used to calculate any age

Answer :B
34.

Carbon -14 is used to determine the age of organic material. The procedure, is based on the formation of .^(14)C by neutron capture in the upper atmosphere. ""_(7)^(14)N+_(0)n^(1) to ""_(6)^(14)C+""_(1)n^(1). ""^(14)C is absorbed by living organisms during photosynthesis. The .^(14)C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of ""^(14)C in the dead being, falls due to the decay.which C^(14) undergoes ""_(6)^(14)C to ""_(7)^(14)N+beta^(-) The half life period of ""^(14)C is 5770 years. The decay constant (lambda) can be calculated by using the following formula lambda=(0.693)/(t_(1//2)) The comparison of the beta^(-) activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle. The method however, ceases to be accurate over periods longer than 30,000 years. The proportion of ""^(14)C to ""^(12)C in livingmatter is 1 : 10^(12). Which of the following option is correct ?

Answer»

In living organisms, CIRCULATION of `.^(14)C` from atmosphere is HIGH so the carbon content is constant in organism
Carbon dating can be USED to FIND out the age of earth crust and rocks
Radioactive absorption due to cosmic radiation is equal to the rate of radioactive decay, hence the carbon content remains constant in living organism
Carbon dating can not be used to DETERMINE concentration of `.^(14)C` in dead beings

Answer :C
35.

Carbon 14 is used to determine the age of organic material. The procedure is based on the formation of 14C by neutron capture in the upper atmosphere ""_(7)N^(14) + _(0)n^(1)rarr ""_(6)C^(14)+ ""_(1)H^(1) ""^(14)C is absorbed by living organism during photosynthesis. The ""^(14)C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of ""^(14)C in the dead being falls due to the decay which C^(14) undergoes. ""_(6)C^(14)rarr ""_(7)N^(14) + _(-1)e^(0) The half life period of ""^(14)C is 5770 years. The decay constant (lambda) can be calculated by using the following formulalambda = (0.693)/t_(1/2)The comparison of the beta –activity of the dead matter with that of carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle. The method however, ceases to be accurate over periods longer than 30,000 years. The proportion of ""^(14)C to ""^(12)C in living matter is 1 : 10^(12 ) A nuclear explosion has taken place leading to increase in concentration of C^(14) in nearby areas. C^(14) concentration is C_(1) in nearby areas and C_(2) in areas far away. If the age of the fossil is determined to be t_(1) and t_(2) at the places respectively, then

Answer»

The age of the fossil will increase at the place where EXPLOSION has taken place and
`t_(1) - t_(2) =1/lambda LN frac (C_(1))(C_(2))`
The age of the fossil will decrease at the place where explosion has taken place and
`t_(1) - t_(2) =1/lambda ln frac (C_(1))(C_(2))`
The age of fossil will be determined to be the same
`t_(1)/t_(2) =frac (C_(1))(C_(2))`

Answer :A
36.

Carbon 14 is used to determine the age of organic material. The procedure is based on the formation of 14C by neutron capture in the upper atmosphere ""_(7)N^(14) + _(0)n^(1)rarr ""_(6)C^(14)+ ""_(1)H^(1) ""^(14)C is absorbed by living organism during photosynthesis. The ""^(14)C content is constant in living organism once the plant or animal dies, the uptake of carbon dioxide by it ceases and the level of ""^(14)C in the dead being falls due to the decay which C^(14) undergoes. ""_(6)C^(14)rarr ""_(7)N^(14) + _(-1)e^(0) The half life period of ""^(14)C is 5770 years. The decay constant (lambda) can be calculated by using the following formulalambda = (0.693)/t_(1/2)The comparison of the beta –activity of the dead matter with that of carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle. The method however, ceases to be accurate over periods longer than 30,000 years. The proportion of ""^(14)C to ""^(12)C in living matter is 1 : 10^(12 ) Which of the following option is correct ?

Answer»

In LIVING organisms, circulation of `""^(14)C` from atmosphere is high so the carbon content is constant in organism
Carbon dating can be used to FIND out the age of earth CRUST and rocks
Radioactive absorption due to cosmic radiation is equal to the RATE of radioactive decay, hence the carbon content REMAINS constant in living organism
Carbon dating cannot be used to determine concentration of `""^(14)C` in dead beings.

Answer :C
37.

Carbon 14 dating method is based on the fact that

Answer»

CARBON -14 FRACTION is the same in all objects
Carbon-14 is highly insoluble
Ratio of carbon -14 and carbon -12 is constant
All of these

Solution :A basis for the `C -14` dating TECHNIQUE
38.

Carbon-14 dating method is that the :

Answer»

Carbon-14 FRACTION is the same in all objects
Carbon-14 is HIGHLY insoluble
Ratio of carbon-14 and carbon-12 are constant
All the above.

ANSWER :C
39.

Carbolic acid is reacted with conc. H_2SO_4 at 300 K gives,

Answer»

2-hydroxybenzenesulphonic acid
3-hydroxybenzenesulphonic acid
4-hydroxybenzenesulphonic acid
2 and 4-phenol sulphonic acid

Answer :A
40.

Carbolic acid is obtained from oxidation of

Answer»

SODIUM salicylate
salicylic acid
toluene
cumene

Answer :D
41.

Carbolic acid is …………………. .

Answer»

PHENOL
Pieric ACID
BENZOIC acid
pheny lacetic acid

SOLUTION :Phenol
42.

Carbohydrates which differ in configuration at the glycosidic carbon (i.e. C_(1) in aldose and C_(2) in ketoses) are called

Answer»

Anomers
Epimers
Diastereomers
Enantiomers

Answer :A
43.

Carbohydrates which give two molecules of mono-saccharides are called disaccharides. These are:

Answer»

MALTOSE
CELLULOSE
MALTASE
LACTOSE

ANSWER :A::D
44.

Carbohydrates that produce two to ten monosaccharide units on hydrolysis are called________.

Answer»

SOLUTION :OLIGOSACCHARIDES
45.

Carbohydrates may be regarded as

Answer»

AROMATIC compounds
alicyclic compounds
polyfunctional compounds
all of these

Answer :C
46.

Carbohydrates , proteins and facts are the thre main components of our food. For a normal person, a balanced diet which contains all these three components in right proportions is recommended for good health. Arjun , a class XII students , however, pointed out that this is not right always. Under special situations, it is not the balanced diet but it is the protein rich diet which is often recommended. Read the above passage and answer the following questions: (i) Why a protein rich diet is recommended for HIV/AIDS patients ? (ii) Why children and expectant mothers need a protein rich diet ? (iii) Person who wish to reduce body weight and heart patients are also recommended protein rich diet. Why ?

Answer»

Solution :(i) The immune system of HIV/AIDS PATIENTS is largely/ completely distroyed. Since REBUILDING immune system besides medication also requires antibodies which are proteins. Therefore, to rebuilt/strengthen immune systems, protein rich diet is recommended.
(ii) Children for their growth and expectant mothers for the growth of their expected infants require building of muscles which requires protein rich foods.
(iii) Protein increases satiety, i.e., you feel fail full for longer periods, thereby reducing the total number of calories eaten per DAY. Further , it increases protein metabolism thereby maintaining lean muscles which is required for weight loss.
A protein rich diet helps to REDUCES the blood pressure as well as the CHOLESTEROL level in the blood. Both these factors are beneficial for heart patients.
47.

Carbohydrates in which large number of monosaccharide units linked to each other by oxides bridges are

Answer»

non-sugars
POLYSACCHARIDES
tetrasaccharides
boht (a) and (B)

SOLUTION :boht (a) and (b)
48.

Carbohydrates may be :

Answer»

sugars
starch
POLYHYDROXY aldehyde/ketones
Compounds that can be HYDROLYSED to sugar

Solution :N//A
49.

Carbohydrates have

Answer»

BITTER taste
sour taste
SWEET taste
some have sweet TEST and some are tasteless

Answer :D
50.

Carbohydrates have the general formula C_X(H_2O)_Y. Which of the following is not a carbohydrate:

Answer»

`C_6H_16O_6`
`C_6H_10O_5)_n`
`C_12H_22O_11`
`C_2H_4O_2`

ANSWER :D