Question

18. Purification of salt (that we get from sea water) can
be done by
(1) Chromatography (2) Centrifugation
(3) Crystallisation (4) Sublimation
19. The value of - -40°C in Kelvin scale is equal to
(1) 233 K
(2) 300 K
(3) 213 K
(4) 313 K
20. The temperature at which a solid melts to become
a liquid at the atmospheric pressure is called its
(1) Freezing point (2) Melting point
(3) Boiling point (4) Triple point
21. Which of the following cell organelles plays an
imnortant role in detoxifying many poisons and​

Answer 1

Answer:I have aslo doubt in this

Explanation:

Answer 2

Answer:

18.(3)

19.we know that, c=273-k

so, -40=273-k

k=273+40=313

so (4).313k is correct