Question

Milk of magnesia can neutralize the effect of

(A) Acid (B) Base (C) Alkali (D) Salt

2. What happens to wool when it is exposed to hot and humid air for a long time?

(A) Turns black (B) Turns yellow (C) Turns red (D) No change in color

3. Wool obtained from dead sheep is called as?

(A) Pulled wool (B) clipped wool (C) burr wool (D) none

4. Tooth paste is

(A) Acidic (B) neutral (C) basic (D) none

5. Find the insoluble hydroxide from below

(A) KOH (B) NaOH

(C) ammonium hydroxide (D) Fe(OH)3

6. The base that is used in the preparation of soap is

(A) Mg(OH)2 (B) NaOH (C) Ca(OH)2 (D) Fe(OH)3

7. Which of the following solutions has pH greater than 7?

(A) Vinegar (B) Rain water (C) lemon juice (D) Baking soda

8. Sericin is a ________ that is given by silk worm to produce a cocoon.

(A) Fat (B) Carbohydrate (C) Protein (D) Mineral

9. Which of the following is not related to silk or its production?

(A) Sorting (B) Moulting (C) Reeling (D) Throwing

10. Which of the following statements is not true about alkalis?

(A) It turns red litmus blue (B) It is sour to taste

(C) It absorbs CO2 gas (D) It contains oxygen and hydrogen​

Answer 1

Answer an Explanation:

1) Milk of magnesia can neutralize the effect of (A) Acid

$\implies$ Milk of magnesia or Mg(OH)₂ has -OH groups on it which can easily react with acidic H⁺ released by acids

2) (D) No change in colour

3) Wool obtained from dead sheep is called as (A) Pulled wool

$\implies$ wool removed from the pelt or fur of a slaughtered sheep

4) Toothpaste is (C) Basic

$\implies$ Toothpaste is made to be basic because, the bacteria present in our mouth produce acidic substances which can be neutralised basic toothpaste

5) (D) Fe(OH)₃ is the insoluble hydroxide

$\implies$ KOH, NaOH and NH₄OH are very much soluble in water but Fe(OH)₃ is not soluble

6) Base used in preparation of soap (B) NaOH

$\implies$ Soaps made from NaOH are firm that is, can be made into bars

7) Solution having pH greater than 7 is (D) Baking soda

$\implies$ pH greater than 7 means solutions having basic nature

$\implies$ Vinegar is acetic acid and has pH < 7

$\implies$ Rain water is generally neutral or pH = 7

$\implies$ Lemon juic is citric acid and has pH < 7

8) Sericin is a (C) protein that is given by silk worm to produce a cocoon

$\implies$ Sericin is a component of silk along with fibroin which is made by silkworms

9) (D) Throwing is not related to silk or its production

$\implies$ Reeling is the process by which many cocoons are reeled together to form one large strand

$\implies$ Sorting is the process by which cocoons are sorted based on the colour, shape, size etc

$\implies$ Moulting is the process when the silkworms stop feeding, stops moving and starts to shed their skin

10) Alkalis are not (B) sour to taste

$\implies$ Bases or alkalis turns red litmus blue

$\implies$ Alkalis are bitter in taste

$\implies$ Alkalis react with CO₂ to form Na₂CO₃

$\implies$ Alkalis generally contain oxygen and hydrogen (Eg: NaOH, KOH etc)

Answer 2

$\large\bf{\underline{\underline{\red{SOLUTION:-}}}}$

1. Milk of Magnesia can neutralized the effect of Acid .

$\bigstar\:\large\rm{\purple{\boxed{(A)\:Acid}}}$

• Sparingly soluble $\rm{Mg(OH)_2}$ forms sol known as Milk of Magnesia .

• It is an alkaline suspension, meaning that it will take cause neutralization when it encounters anything acidic .

• This is why it makes an excellent antacid, as it neutralizes excess Hydrochloric acid (HCL) when swallowed .

2. When wool is exposed to hot and humid air for a long time, it doesn't change in colour .

$\bigstar\:\large\rm{\orange{\boxed{(D)\:No\:change\:in\:colour}}}$

3. Wool obtained from dead sheep is called as Pulled wool .

$\bigstar\:\large\rm{\green{\boxed{(A)\:Pulled\:wool}}}$

4. Toothpaste is Basic .

$\bigstar\:\large\rm{\pink{\boxed{(C)\:Basic}}}$

5. $\rm{Fe(OH)_3}$ is the insoluble hydroxide .

$\bigstar\:\large\rm{\blue{\boxed{(D)\:Fe(OH)_3}}}$

6. The Base used in the preparation of soap is NaOH .

$\bigstar\:\large\rm{\purple{\boxed{(B)\:NaOH}}}$

7. Solution having pH greater than 7 is Baking soda .

$\bigstar\:\large\rm{\orange{\boxed{(D)\:Baking\:Soda}}}$

8. Sericin is a protein that is given by silk worm to produced a cocoon .

$\bigstar\:\large\rm{\green{\boxed{(C)\:Protein}}}$

9. Throwing is not related to silk or its production .

$\bigstar\:\large\rm{\pink{\boxed{(D)\:Throwing}}}$

10. Alkalis are not sour to taste .

$\bigstar\:\large\rm{\blue{\boxed{(B)\:it\:is\:sour\:to\:taste}}}$