what will happen if : a)In place of zinc granules,some amount of zinc dust is taken in the test tube? b)Instead of dilute sulphuric acid,dilute hydrochloric acid is taken? c)Instead of dilute sulphuric acid,dilute nitric acid is taken? d)in place of zinc,copper turning are taken? e)Sodium hydroxide is taken in place of dilute sulphuric acid.
Answers
In the first case a)
If in place of zinc granules,some amount of zinc dust is taken in the test tube, then it would result in the formation of hydrogen gas and thus it speeds the reaction rate making it increase.
In second case b)
If Instead of dilute sulphuric acid,dilute hydrochloric acid is taken,then it would result in the formation of zinc chloride instead of zinc sulphate. Thus when it reacts along with hydrogen gas it doesn't posses any change in the reaction rate.
In the third case c)
If Instead of dilute sulphuric acid,dilute nitric acid is taken,then it would result in the formation of zinc nitrate and hydrogen gas.
In the fourth case d)
If in place of zinc,copper turning are taken, then Copper will not react with dilute acids under normal condition. So it results in no reaction taking place.
In the last case e)
If Sodium hydroxide is taken in place of dilute sulphuric acid, then Sodium zincate will be formed as it will be heated in the process thus increasing the reaction rate and also the hydrogen formation.
Hope you understand! :-)
Answer:
(a) If in the place of zinc granules, the same amount of zinc dust is taken in the test tube then the rate of the reaction will increase and the reaction will take place more quickly. This is because the surface area per unit volume of powder is more than that of the zinc granules and hence the powder will provide more surface area for the reaction to take place.
(b) If in place of dilute sulphuric acid, we use dilute hydrochloric acid then the reaction will take place as usual because in both cases we are mixing a strong acid with a metal.
(c) If in the place of zinc, copper turning is taken then also the reaction will proceed in a similar way and would lead to the evolution of hydrogen gas as here we are only replacing one metal with another metal in the reactant side of the reaction. In this case, also we are mixing a strong acid with a metal.
(d) If sodium hydroxide is taken in place of dilute sulphuric acid and the tube is heated then the metal will react with the base to form the corresponding salt and will evolve hydrogen gas as per the following reaction:
Zn+2NaOH→Na
2
ZnO
2
+H
2