(a) why does an aqueous solution of an acid conduct electricity?
(b) which has higher pH value, concentrated or dilute solution of HCl?
(c) why should water never be added to conc. H2SO4 during dilution?
(a) why does an aqueous solution of an acid conduct electricity?
(b) which has higher pH value, concentrated or dilute solution of HCl?
(c) why should water never be added to conc. H2SO4 during dilution?
(a) An aqueous solution of acid conducts electricity because of the presence of H+ ions (acids furnish H+ ions in water).
(b) A dilute solution of HCl has higher pH value than concentrated HCl.
(c) It is always advised to add acid to water than water to acid. This is because the reaction between acid and water is highly exothermic and so produces lot of heat. Hence, when water is added to acid, it results in vigorous boiling of the solution and the amount of heat produced is so large that it splashes the acid out of the container, which can result in acid burns. On the other hand, when we add acid to water, it is like adding a concentrated solution to water in small amounts. So comparatively lesser amount of heat is released. This is why for dilution, water should not be added to concentrated sulphuric acid. Instead concentrated sulphuric acid should be added in small lots to water.
(a) An aqueous solution of acid conducts electricity because of the presence of H+ ions (acids furnish H+ ions in water).
(b) A dilute solution of HCl has higher pH value than concentrated HCl.
(c) It is always advised to add acid to water than water to acid. This is because the reaction between acid and water is highly exothermic and so produces lot of heat. Hence, when water is added to acid, it results in vigorous boiling of the solution and the amount of heat produced is so large that it splashes the acid out of the container, which can result in acid burns. On the other hand, when we add acid to water, it is like adding a concentrated solution to water in small amounts. So comparatively lesser amount of heat is released. This is why for dilution, water should not be added to concentrated sulphuric acid. Instead concentrated sulphuric acid should be added in small lots to water.
