Separation of substances Worksheet-1

Separation of substances Worksheet-1

 

Fill in the blanks:

  1. When two or more pure substances are mixed together in such a way that each component retains its properties is called a ______.
  2. ______ method of separation is based on the property that grains are heavier than husk and hay.
  3. A solution in which no more solute can be dissolved at a fixed temperature is called a _____.
  4. Formation of dew in nature is due to ______ of moisture in the air.
  5. In lemon water, lemon juice is a ______. (solute/solvent)

 

Multiple-Choice Question:

  1. In a flour mill, impurities like husk and stones are removed from wheat before grinding it by:

(A) Threshing      (B) Winnowing    (C) Sieving           (D) Hand-picking

 

  1. Common salt is obtained from:

(A) sea water       (B) river water     (C) lake water     (D) spring water

 

  1. Salt can be obtained from sea water by:

(A) filtration                                      (B) decantation  

(C) Centrifugation                            (D) Evaporation

 

  1. Mixtures are:

(A) impure substances                   (B) pure substances

(C) Molecules                                   (D) none of these

 

  1. Fractional distillation is used to separate:

(A) solids from solids                       (B) solids from liquids

(C) liquids from liquids                   (D) none of these

 

  1. A pure substance is made up of:

(A) Only one kind of molecules     (B) Two or more kinds of molecules

(C) Different types of molecules    (D) None of these

 

  1. Brass is a mixture of ________and ________.

(A) Copper, Zinc  (B) Copper, tin    (C) Copper, iron  (D) Copper, Chromium

 

Answer key:

  1. Mixture
  2. Winnowing
  3. saturated solution
  4. Condensation
  5. Solute
  6. (C)
  7. (A)
  8. (D)
  9. (A)
  10. (C)
  11. (A)
  12. (A)