Question

Take a glass of water, pour the substances given below and stir them properly. After that observe the glass properly and classify soluble and insoluble substances on the basis of observation.
1. Sugar(half teaspoon) 2. Mustard seeds(half teaspoon) 3.Two or three drops of coconut oil. ​

Answer 1

AnswEr:

Case 1). What will happen if we pour half tea spoon of sugar in a glass of water?

→ It will dissolve in water and a true solution will form. [Sugar is soluble.]

True solution properties -

• It is homogeneous mixture, having uniform properties.
• We can't separate solute and solvent from it by physical techniques.
• The size of solute is too small (1 nm) which can't be seen by naked eyes.

Case 2). What will happen if we pour half tea spoon of mustard in a glass of water?

→ It won't dissolve in water and a suspension will form. [Mustard seeds are insoluble.]

Suspension properties -

• It is a heterogeneous mixture with non uniform properties.
• We can separate solute and solvent from it by physical techniques. [Handpicking.]
• Solute can be seen with naked eyes.

Case 3). What will happen if we pour three drops of coconut oil in a glass of water?

→ It won't dissolved and oil will rise up on the top of water. [Oil is insoluble in water.]

Reason: The density of oil is lesser than the density of water, so it will rise up.

Answer 2

$\huge\mathtt\red{Question}$

Take a glass of water, pour the substances given below and stir them properly. After that observe the glass properly and classify soluble and insoluble substances on the basis of observation.

1. Sugar(half teaspoon)

2. Mustard seeds(half teaspoon)

3.Two or three drops of coconut oil.

$\huge\mathtt\red{Answer}$

1. It will dissolve in water and a true solution is formed.

2. It will not dissolve in water and a suspension will form.

3. It will not dissolve and we can observe the oil droplets in the upper layer.

$\huge\mathtt\red{Reason}$

1. It is a homogeneous mixture having a uniform property and we can separate solute and solvent by physical techniques.

2. It is a heterogeneous mixture with non uniform properties and we can also separate solute and solvent by physical techniques.

3. The density of oil is lesser than water, so it float on water.