Question

Why is ice at 273k more effectivein cooling thanvwater at same temperature?

Answer 1

Explanation:

15. Which of the following salts can produce only two types of radicals?

Options:

(a)

NaKCO3

(b)

CaOCl2

(c)

NH HSO 4 4

(d)

Na NH HPO  4 4 

16. The weight of an empty China dish is 39 g and when a saturated solution of potassium

nitrate is poured into it, its weight is 108 g at

50C

. After evaporating the solution to

dryness, if the weight of the dish along with the crystals is 72 g then the solubility of

potassium nitrate at

50C

is _____.

Options:

(a) 83.9

(b) 95.6

(c) 91.6

(d) 87.4

17. If the roots of the quadratic equation

2

ax bx c    0

are



and



, then the equation

whose roots are

2 

and

2



is

Options:

(a)

 

2 2 2 2 a x b ac x c     2 0

(b)

2 2 2 2 a x b x c    0

(c)

 

2 2 2 2 a x b ac x c     2 0

(d)

 

2 2 2 2 a x b ac x c     2 0

18. If

2 2

Answer 2

Ice at 273 K will absorb heat energy or latent heat from the medium to overcome the fusion to become water . So ice is more effective in cooling than water at the same temperature .