Identification of Acids and Bases

IMPORTANT

Identification of Acids and Bases: Overview

This topic explains concepts such as Indicators, Acid-Base Indicators, Lichens, Litmus, etc.

Important Questions on Identification of Acids and Bases

HARD
IMPORTANT

Complete the following table:

Indicator Solution Colour
Litmus Lemon juice  
Litmus Ammonium hydroxide  
Phenolphthalein Ammonium hydroxide  
Phenolphthalein Hydrochloric acid  
Turmeric juice Soap solution  
Turmeric juice Orange juice  
Red-cabbage juice Soap solution  
Red-cabbage juice Hydrochloric acid  

 

MEDIUM
IMPORTANT

The yellow colour of turmeric changes to red on addition of soap solution. When substance P is added to turmeric, there is no change in colour.

Which of the following is definitely true about substance P?

MEDIUM
IMPORTANT

An indicator is used to determine certain chemical properties of a substance.

EASY
IMPORTANT

Identify the indicator given below and write the nature of the solution on test tubes A and B.

Question Image

EASY
IMPORTANT

If China rose petal is put in the solution of Milk of Magnesia, it will change its color from light pink to_____.

MEDIUM
IMPORTANT

Which color change is applicable when china rose petals is put in the solution of H2CO3?

EASY
IMPORTANT

What will happen if turmeric paper is made in contact with caustic soda solution?

EASY
IMPORTANT

When turmeric paper is placed in contact of HCl, it will_____.

MEDIUM
IMPORTANT

You are given the following solutions,

(i) salt solution (ii) soda water and (iii)shampoo solution

How will you identify if the solution is acidic, basic or neutral using red cabbage ?

MEDIUM
IMPORTANT

Peel a beet root with the help of peeler and cut into small pieces with the help of knife. Take these pieces in a mortar and crush well and obtain extract by adding water. Filter the extract through a filter paper and collect filtrate. Take four transparent glasses and label it as A, B, C, D and write your observation in table given.

S.No. Glass Solution Observations
1. A Vinegar  
2. B Soda water  
3. C Lemon juice  
4. D Baking soda solution  

 

MEDIUM
IMPORTANT

Describe how the colour of universal indicator changes in different types of solutions.

MEDIUM
IMPORTANT

A solution turns methyl orange into yellow the approximate pH of solution is

EASY
IMPORTANT

What happens, when methyl orange solution mixed with HCl?

EASY
IMPORTANT

The indicators which turn red in acid solution are:

EASY
IMPORTANT

Which of the given substance is an acid/base indicator:

EASY
IMPORTANT

Which of the following is not an acid-base indicator?

EASY
IMPORTANT

Litmus solution is extracted from

EASY
IMPORTANT

_____ is an indicator made from the lichens.

EASY
IMPORTANT

The litmus paper or the litmus solution is obtained from _____ plant.

MEDIUM
IMPORTANT

Indicators that are synthesised in the laboratory are known as _____ indicators.