68.

69.

70.

71.

72.

73.

74,

75.

An old wooden stool was found to give 7.7 disintegrations g~ min . If a fresh wooden
material showed a C14 (t; 2=5730 years) activity of 15.4 disintegrations g~ 0107-71, age of
the sample is :

(മ) 3433 years (B) 8271 years (ಲ) 5732 years (D) 9144 years

Choose the odd function among the following :
(ಹಿ) cosx ‏زم‎ நீன்ட (ಲ) coshx (>) €भ

The Van Der Waals constants of a gas are : a=0.7 dm® atm.mol~2 and b=0.02 dm3mol~1.
The critical temperature of the gas is :

A) 6K B 126K © 006K (D) 104K

Choose the incorrect relation from the following thermodynamic equations :

© ‏ماقا عل‎ உண लि),
லல © कि. कि),

The molar ionic conductance at infinite dilution of lithium chloride (LiCl) is found to be
8,972 775 722 7701-71, 7" the molar ionic conductance of Li tion is 3.87 mS m2 mol 1, the molar
ionic conductance of chloride ion would be :

(ಹಿ) 12.79 75 72 776] 1 ൫ 4.33 75 72 7701-1
(೦) 231710-45 ‏اممد عم‎ 1 (D) 505x1074S m2 mol~1

If k, the rate constant for the decomposition of N,Og is 5x 10~ s 71, the time required for the
N,Oj concentration to be 50% of the original value is :

(A) 138×103 ‏و‎ (೫ 2x10%s
€) 6.02x10%s (D) None of the above

The correct order of efficacy for coagulating a lyophobic sol. is given by :
(A) ‏ولا‎ > BaZt > Ca2t > Nat < ۰+ 8 BaZt > Mg2+ >Ca2t >K+>Nat
€) Ca?t>Ba?t>Mg?* >K*>Nat (D) Mg?*>Ca?t>Ba?t >Nat >K*

The dissociation constant of acetic acid is 2x 1075 at 25°C. What would be the pH of an
aqueous solution obtained by mixing 0.3 g of acetic acid and 4.1 g of sodium acetate and
making a 500 ml solution ?

(ಹ) 5.8 © 9
(~) 5 (D) None of the above

22/2019 10 A