Table 2.1 class 10 science solutions

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Table 2.1 class 10 science solutions belongs to chapter 2 Acids, Bases and Salts.In this post, we will discuss colour change of different solutions with given indicators.

We know that substances or solutions are classified as acids  or bases and they show different colour change with different indicators.

Table 2.1 class 10 science solutions

Table 2.1Class 10 Science

We have given following solutions to test with  indicators and identify whether they are acids or bases.

Given solutions

Solutions
`HCl`
`H_2SO_4`
`HNO_3`
`CH_3COOH`
`NaOH`
`Ca(OH)_2`
`KOH`
`Mg(OH)_2`
`NH_4OH`

 

 

Table 2.1Class 10 Science

Sample solution Red litmus solution Blue litmus solution Phenolphthalein solution Methyl orange solution

 

Table 2.1 Class 10 Science Solutions

Now, we take given solutions in separate watch glasses and add a few drops of indicators given in the table 2.1 and observe the change in the colour.

Sample solution Red litmus solution Blue litmus solution Phenolphthalein solution Methyl orange solution
`HCl` No change Changes to red Colourless Changes to red
`H_2SO_4` No change Changes to red Colourless Changes to red
`HNO_3` No change Changes to red Colourless Changes to red
`CH_3COOH` No change Changes to red Colourless Changes to red
`NaOH` Changes to blue No change Change to light pink Change to yellow
`Ca(OH)_2` Changes to blue No change Change to light pink Change to yellow
`KOH` Changes to blue No change Change to light pink Change to yellow
`Mg(OH)_2` Changes to blue No change Change to light pink Change to yellow
`NH_4OH` Changes to blue No change Change to light pink Change to yellow

 

So given solutions show change in colour with indicator. We can classify them into acids and bases on the basis of colour change.

Table 2.1 Class 10 Science observation

  • `HCl`,  `H_2SO_4` , `HNO _3` and `CH_3COOH` show no change in colour with red litmus solution.

 

  • `HCl`,  `H_2SO_4` , `HNO _3` and `CH_3COOH`show red colour with blue litmus solution.

 

  • `HCl`,  `H_2SO_4` , `HNO _3` and `CH_3COOH` remain colourless with phenolphthalein solution.
  • `HCl`,  `H_2SO_4` , `HNO _3` and `CH_3COOH`show red colour with methyl orange solution.

So, these solutions are acids.

  • `NaOH` , `Ca(OH)_2` ,`KOH` , `Mg(OH)_2`  ,  `NH_4OH` show blue colour with red litmus solution.
  • `NaOH` , `Ca(OH)_2` ,`KOH` , `Mg(OH)_2`  ,  `NH_4OH`show no change in colour with blue  litmus solution.
  • `NaOH` , `Ca(OH)_2` ,`KOH` , `Mg(OH)_2`  ,  `NH_4OH`show light pink colour with phenolphthalein solution.
  • `NaOH` , `Ca(OH)_2` ,`KOH` , `Mg(OH)_2`  ,  `NH_4OH` show yellow colour with methyl orange solution.

So, these solutions are bases.

 

We know solutions that release hydrogen ions (`H^+`)  water are called acids and solutions that release hydroxyl ions (`OH^-`) in water are called bases.

 

Important Questions based on table 2.1 Class 10 Science

 

1.How do acids react with red litmus paper?

  Ans – Acids do not react with red litmus paper.

2.Why does litmus turn red in acid?

 Ans- Litmus is naturally blue or purple obtained by Phaeophyta (lichens).Hydrogen ions from acids react with blue litmus causing it to turn red.

3.What are acids and bases according to Arrhenius theory?

 Ans – According to Arrhenius theory, Acids are the substances that release hydrogen ions in aqueous solutions and bases release hydroxyl ions.

4.What do all acids and bases have in common?

 Ans – All acids and bases release ions in aqueous solution. Acids release hydrogen ions and bases release hydroxyl ions.

5.How  do acids and bases react with each other?

 Ans- Acids and bases neutralize each other and the reaction is called neutralisation reaction.in this reaction salt and water are formed.

6.What are indicators in acids and bases?

 Ans- Indicators are the substances used to identify the given solution is acidic or basic. They change their colour on the basis of PH of the given solution.

7.Name the indicator used in table 2.1to classify the given solutions as acids or bases?

 Ans – Red litmus, blue litmus , phenolphthalein and methyl orange

8.Which solutions turn red when added to blue litmus solutions?

Ans – HCl , H2SO4 , HNO3 and CH3COOH

9.How do acids react with phenolphthalein solution?

 Ans-  Acids remain colourless with phenolphthalein solution.

10.What is the characteristics of acids?

Ans- Acids release hydrogen ions(`H^+`) in water.

11.What is the characteristics of bases?

Ans – Bases release hydroxyl ions (`OH^-`) in water.

 

MCQs based on table 2.1 Class 10 Science Solutions

 

1.What colour change does red litmus solution when added into acids?

  1. Blue
  2. Red
  3. Yellow
  4. No change

   Correct answer- (d) No change

 

2.Why does litmus solution turn red in the presence of an acid?

  1. Litmus naturally gets turn into red in acid
  2. Litmus absorbs hydrogen ions and turn into red.
  3. Litmus react with oxygen
  4. All of the above

    Correct answer -(b)Litmus absorbs hydrogen ions and turn into red.

 

3.What do bases release in aqueous solutions according to Arrhenius?

  1. Oxygen ion
  2. Hydrogen ion
  3. Hydroxyl ion
  4. None of the above

   Correct answer -(c) Hydroxyl ion

 

4.What is common characteristics of all acids and bases?

  1. They are colourless
  2. They release ions in aqueous solution
  3. They have sour taste
  4. They turn blue litmus into red

   Correct answer-(b) They release ions in aqueous solutions

 

5.What is the name of reaction when acid reacts with base?

  1. Combination reaction
  2. Decomposition reaction
  3. Neutralization reaction
  4. Displacement reaction

    Correct answer-(c) Neutralization reaction

 

6.Which solution turn red when added to blue litmus solution?

  1. Bases 
  2. Acids
  3. Both 
  4. None of the above

   Correct answer-(b) Acids

7.How do acids react with phenolpthalein solution?

  1. Acids turn into pink
  2. Acids turn into red
  3. Acids remain colourless
  4. Acids turns into yellow

   Correct answer-(c) acids remain colourless

8.What is the specific characteristics of all acids?

  1. Release hydrogen ions
  2. Release hydroxyl ions
  3. Have bitter taste
  4. All of the above

    Correct answer -(a) release hydrogen ions

9.What is the specific characteristics of bases?

  1. Release hydrogen ions
  2. Release hydroxyl ions
  3. Have sour taste
  4. All of the above

    Correct answer- (b) release hydroxyl ions

 

Quiz based on Table 2.1 Class 10 Science

 

 

Related Topics

  1. Characteristics of ionic compounds

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