A student was given a white powder and asked to study the action of water on it. When the student added some water to this white powder, it set into a hard mass in about half an hour.
(a) What is the common name and chemical formula of white powder?
(b) Name its two uses.

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Solution

(a) The white powder is calcium sulphate hemihydrate( ${CaSO}_{4} . \frac{1}{2} H_{2} O$ ). Commonly known as plaster of paris.

(b) Uses of plaster of paris:
1. used for the treatment of fractured/broken bones
2. used for making toys, making surfaces smooth and for decoration purposes

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A student was given a white powder and asked to study the action of water on it. When the student added some water to this white powder, it set into a hard mass in about half an hour. (a) What is the common name and chemical formula of white powder? ​(b) Name its two uses.

(a) The white powder is calcium sulphate hemihydrate(CaSO4.12H2O). Commonly known as plaster of paris. (b) Uses of plaster of paris: 1. used for the treatment of fractured/broken bones 2. used for making toys, making surfaces smooth and for decoration purposes

A student was given a white powder and asked to study the action of water on it. When the student added some water to this white powder, it set into a hard mass in about half an hour.
(a) What is the common name and chemical formula of white powder?
(b) Name its two uses.

(a) The white powder is calcium sulphate hemihydrate( ${CaSO}_{4} . \frac{1}{2} H_{2} O$ ). Commonly known as plaster of paris.

(b) Uses of plaster of paris:
1. used for the treatment of fractured/broken bones
2. used for making toys, making surfaces smooth and for decoration purposes