Question

Observe the following table and answer the questions given below. The table contains the aqueous solutions of different substances with the same concentrations and their respective pH values.

Sample (solution) (Acid/Base)	A	B	C	D	E	F	G	H
pH value	8.1	1.1	5.5	13.6	3.5	9.5	7	10

(i) Which one of the above acid solutions is the weakest acid ? Give a reason. 

(ii) Which one of the above solutions is the strongest base ? Give a reason. 

(iii)Which of the above two produce maximum heat when they react ? What is that heat energy called ?

Answer 1

(i) Weakest acid is 'C' Because its pH value is less than 7 and it is near to 7. 

(ii) Strongest base is 'D' Because its pH value is near to 14. 

(iii) B, D produce maximum heat when they react. This heat energy is known as neutralization energy.

(iv) 'G' has the pH equal to that of the distilled water. These type of solutions are known as neutral solutions.