Question

Three substances X, Y and Z are found in a mixture.
i) X is a solid and is heavier than both Y and Z.
ii) Y and Z are liquids.
iii) Z is a liquid which is lighter than both X and Y.

After sedimentation of the mixture, which amongst the components can be decanted out first?

• A. X
• B. Y
• C. Z
• D. Both X and Y

Answer 1

The correct option is C Z

Decantation is a process where the lighter liquid layer will be poured out leaving the insoluble heavier substances behind, when an insoluble solid-liquid mixture is left undisturbed for sometime.

In the given mixture, X being a heavier solid which will settle down at the bottom. Although Y and Z are liquids, Z is lighter than Y and hence, floats above Y. So, while decanting the mixture, it is liquid Z which will be poured out first.