Question 12 Marks
Account for the following :
i. State the relation between hydrogen ion concentration of an aqueous solution and its pH .
ii. An aqueous solution has a pH value of 7.0. Is this solution acidic, basic or neutral.
iii. Which has a higher pH, 1 M HCl or 1 M NaOH solution?
iv. Tooth enamel is one of the hardest substance in our body. How does it undergo damage due to eating chocolates and sweets? What should we do to prevent it?
v. How do ${H}^{+}$ions exist in water?
i. State the relation between hydrogen ion concentration of an aqueous solution and its pH .
ii. An aqueous solution has a pH value of 7.0. Is this solution acidic, basic or neutral.
iii. Which has a higher pH, 1 M HCl or 1 M NaOH solution?
iv. Tooth enamel is one of the hardest substance in our body. How does it undergo damage due to eating chocolates and sweets? What should we do to prevent it?
v. How do ${H}^{+}$ions exist in water?
Answer
View full question & answer→i. Hydrogen ion concentration of an aqueous solution is inversely proportional to its pH .
ii. The solution is neutral.
iii. 1 M NaOH solution has higher pH because base have higher pH value than acids.
iv. Tooth enamel gets corroded slowly when pH in the mouth is below 5.5. Acid is produced in mouth due to degradation of food which is partially hydrolysed by saliva. But if excess acid is produced, it causes tooth decay. It can be prevented by using tooth paste which are generally basic.
v. ${H}^{+}$ions exist in water as ${H}_{3}{O}^{+}$ions.
ii. The solution is neutral.
iii. 1 M NaOH solution has higher pH because base have higher pH value than acids.
iv. Tooth enamel gets corroded slowly when pH in the mouth is below 5.5. Acid is produced in mouth due to degradation of food which is partially hydrolysed by saliva. But if excess acid is produced, it causes tooth decay. It can be prevented by using tooth paste which are generally basic.
v. ${H}^{+}$ions exist in water as ${H}_{3}{O}^{+}$ions.