Surfactants

Q. Which of the following materials do not have lustre?

1. Iron
2. Copper
3. Aluminium
4. Wood

Q.

Name four items of daily use which have been made using the knowledge of chemistry?

Q. Choose the lustrous substance from the given options.

1. Copper bell
2. Wooden table
3. Plastic chair
4. Paper boat

Q.

What are transparent objects? give their examples.

Q.

Arrange the following substances in the increasing order of hardness.

1. Sponge
2. Brick
3. Iron rod
4. Diamond

Q.

What is the term given for the molecular attraction that holds two unlike substances together?

1. Adhesion

2. Absorption

3. Adsorption

4. Cohesion

Q. Dinesh's village is flooded with water due to heavy rain, so he planned to make a boat for transportation. Which of the following material should he use to make a boat?

1. Glass
2. Wood
3. Rock
4. Marble

Q. Which of the given compounds undergoes electrolytic decomposition reaction?

1. None of the above

2. $AgCl\left(s\right)$

3. $2H_{2}O\left(l\right)$
   

4. $CuC{O}_3\left(s\right)$

Q. is insoluble in water.

1. Lemon juice
2. Sugar
3. Sawdust
4. Salt

Q. Which among the following object is made using only a single type of material?

1. Pencil
2. Paper bags
3. Hammer
4. Kitchen knife

Q. Which among the following is hard in nature?

1. Tooth paste
2. Sponge
3. Diamond
4. Foam

Q. Give examples of the types of following chemical reactions.
(a) Combination reaction
(b) Displacement reaction

Q.

Beewax is a _______ (transparent/ translucent) liquid.

Q. Which of the following objects can be made from wood?

1. Phone, laptop and chair
2. Chair, bench and table
3. Shirt, barbie doll and phone
4. Chair, bench and purse

Q. Cite an example with chemical equation where a chemical change is associated with change in color.

Q.

What happens when water is added to kerosene?

1. Water floats above kerosene.

2. Kerosene floats above water.

3. They both mix well.

4. Kerosene reacts with water.

Q. A leaf on water while a coin in it.

1. dissolves
2. sinks
3. floats
4. dissapears

Q. Find the odd one out from the following:
Gold, Soil, Aluminum, Silver, Platinum, Iron

1. Aluminum
2. Silver
3. Soil
4. Iron

Q. The reaction $2H_{2}O\to 2H_2+O_2$ is an example of

1. Decomposition reaction
2. Double displacement reaction
3. Displacement reaction
4. Combination reaction

Q. Identify the substances that are prepared by chemical processing.

1. Toothpaste
2. Soaps
3. Neem twigs
4. Pomegranate rind

Q. Soaps and detergents are called as surfactants.

1. False
2. True

Q. Identify the object that sinks in water.

1. Leaf
2. Sponge
3. Iron nail
4. Paper

Q. When the oil is spread on paper then the objects on the other side:

1. can be seen clearly.
2. appear more bright.
3. can be vaguely seen.
4. can't be seen.

Q. Of the following, the commonly used laboratory desiccator is:

1. $K_{2}C{O}_3$
2. $CaC{l}_2$
3. $NaCl$
4. $CaC{O}_3$

Q. When copper turnings are added to silver nitrate solution, a blue coloured solution is formed after some time. Which of the following option justifies the observation?

1. $\text{Cu}$ is oxidised to ${\text{Cu}}^{2+}$.
2. $\text{Cu}$ is reduced to ${\text{Cu}}^{2+}$
3. Copper forms a blue coloured complex with ${\text{AgNO}}_3$
4. Copper oxidises silver from the solution.

Q. most lustre metal

Q. Which of the following are surfactants?

1. soap bar
2. washing powder
3. shampoo
4. liquid soap
5. detergent
6. oil
7. water
8. salt

Q.

Which among the following substances is insoluble in water?

1. Vinegar
2. Sugar
3. Salt
4. Sawdust

Q. Out of the below mentioned properties, which is the most important when making a hammer?

1. Heat resistance
2. Lustre
3. Hardness
4. Softness

Q. Which among the following objects will not float on water?

1. A metal key
2. A wooden cork
3. A sheet of paper
4. A leaf