Section-A
1)Tincture of iodine has antiseptic properties.This solution is made by dissolving: (1)
a)Iodine in potassium iodide. B) Iodine in Vaseline
c) Iodine in water. D) Iodine in alcohol
2)The chemical symbol for Sodium is: (1)
a)Ni. B)Na
c)No. d)Sd
In the following questions two statements are given :one labelled assertion and other labelled reason.
select the correct answer for ab,c,d as given below:
a)Both A and R are true and R is correct explanation of assertion.
b) Both A and R are true but are is not correct explanation of assertion.
C) A is true but R is false.
d) A is false but R is true.
3)Assertion (A): milk and starch solution will show tyndall effect.
Reason ®:because this both contain colloidal particles which cannot be seen with naked eye but big
enough to scatter a beam of light (1)
4)Assertion (A):The size of an atom is very small.
Reason: Atoms of most elements do not exist independently.(1)
Section-B
5)Show diagramatically the separation of mixtures by sublimation.(3)
6)Write applications of centrifugation..(3)
7) Define a solution.Give an example of gas :1)Gas in liquid solution 2)Gas in solution.(3)
8)Name the technique to separate.(3)
Answers
Answer:
1. Iodine in alcohol
2. Na
3. Both A and R are true and R is the correct explanation of assertion
4.both A and R are true and R is not correct explanation of assertion
5. the above photo shows the sublimation of camphor
6.centrifugation is a process in which a liquid is spinning at high speed with a machine called centrifugate in this process the lighter liquid flows happen the heavier liquid comes down certification is used to separate milk from cream in the diary
7.solution is a mixture of solute in a solvent .carbonated drinks like Coca Cola is an example of gas in liquid solution .gas is solute and liquid solvent .all gases in the atmosphere is gas in gas solution .here nitrogen is solvent and all gases are solutes
8. there are many techniques to separate they are separating by suitable solvent ,separating by using with a magnet ,separating by using filter paper ,separated by evaporation ,separated by crystallization ,separating by chromatography, separated by distillation and fractional distillation ,operating by separating funnel
