The rate of sedimentation is increased by adding ____ to the water.
Alum is added to purify water as Aluminium Sulphate. It is a coagulant. When Alum is added to the muddy water, the mud particles accumulate to settle down.
The process followed to separate grains form the stalks is called
Look at the picture below and find out the method by which components in the mixture are separated.
Sieving is defined as a method in which two or more components of different sizes are separated from a mixture on the basis of the difference in their sizes. Thus, it cannot separate two substances in a mixture which have the same size. For example, it cannot separate a mixture of chalk powder from flour.
When a bottle of soda water is opened, carbon dioxide escapes, producing a fizz. This is due to:
Butter is separated from curd by the process of:
Which of the following is not characteristic of solids?
When we blow air into the balloon, it inflates because:
Select a good conductor of heat among the following options.
The process in which particles of a solid settle down in a liquid is known as:
Which of the following is essential to perform winnowing activity?
Wind winnowing is an agricultural method developed by ancient cultures for separating grain from straw. It can also be used to remove pests from stored grain. Winnowing usually follows threshing in grain preparation.
Handpicking method is effective in:
Which of the following is an example of irreversible change?
The picture below shows a mixture of beads and flour in a bowl.
Q. Rehan wants to separate the beads from the flour in the bowl. What separation method can he use?
Saimaa is making herself a cup of coffee. She adds in sugar to her coffee. What will happen if she continues adding more coffee powder to her drink?
Which of the following is incorrect?
Study the picture below and answer the questions that follow.
Q. What is the name of the process taking place in the picture?
The picture below shows a teabag in a glass of water.What is the function of the teabag?
Fill in the blanks below, using the helping words provided in the box. Each word can be used only once.
filtration, soluble, permanent, substance, reversible, temporary
1. When a sliced apple turns brown, a new has formed.
2. Burning plastic is a change.
3. We can separate insoluble solids from liquids by .
4. A change takes place when a material that has undergone a change can return to its original form.
5. When a solid is able to dissolve in water, we say that it is in water.
6. A change is when no new substances are formed.
Q. Choose the correct sequence:
Samarth mixed the following things in a bowl, then carried out the following steps.
Q. Which two steps are not in a correct sequence?
Step 1: Remove the pencils by sorting them by hand.
Step 2: Use a magnet to separate the iron nails.
Step 3: Pour water into the mixture of sand and sugar.
Step 4: Remove the copper nails by sorting by hand, or by using a sieve.
Step 5: Use filtration to separate the sand.
Step 6: Use evaporation to obtain the sugar.
Match the objects given below with the materials from which they could be made. Remember, an object could be made from more than one material and a given material could be used for making many objects.
Q. Choose the correct sequence