Questions on Practical chemistry
CLASS 10 ICSE
1. A compound 'X' is a water soluble salt. When Lead nitrate solution is added to the aqueous solution of the salt 'A', it gives a white ppt. which dissolves on heating.
And salt 'A' gives golden yellow flame in flame test. Name of the salt 'A' is-
Ans: Sodium chloride
2. When a highly soluble gas 'G' is dissolved in water, it forms it's aqueous solution. This aqueous solution gives a deep blue solution when added in excess to Copper sulphate solution. Name of the gas 'G' is ____________.
Ans: Ammonia gas
3. Compound 'C' is a preferred reactant in the laboratory preparation of Ammonia gas from Ammonium salts. State the appropriate observation when Sodium hydroxide solution is added to the aqueous solution of the salt, formed when Compound 'C' is neutralized by dil.HCl ___________
Ans: white ppt
4. Salt 'M' is a deliquescent compound that can be prepared by direct combination of a metal and a highly reactive non-metal. When it's salt solution is treated with Sodium hydroxide solution gives a reddish brown ppt. The name of the salt is _______________
Ans: Ferric chloride
5. When an oxidizing agent, which is black powder, is heated with a conc. Acid 'A' gives a greenish yellow gas. Then identify that acid 'A'.
_____________
Ans: Conc HCl
6. Dilute Hydrochloric acid reacts with a salt ' T' to produce a colourless gas. When this gas is passed into lime water, it turns milky. That gas decolourizes acidified Potassium permanganate solution. Identify the anion present in the salt 'T' _______________
Ans: Sulphite ion
7. A chemical compound 'Q' on heating leaves a yellow residue fused with glass test tube and gives reddish brown vapours. What is the observation when that yellow residue is heated with Ammonia gas? ____________
Ans: leaves greyish residue
8. State one appropriate observation when Ammonium hydroxide is added in small amount to Zinc sulphate solution, then in excess._________________
Ans: Gelatinous white ppt and it dissolves in excess Ammonium hydroxide
9. A platinum wire is dipped in Calcium chloride solution and introduced into the flame of a burner. The colour of the flame is ____________
Ans: Brick red colour flame
10. Identify the hydrated salt which on heating loses it's water of crystallization and turns it's colour from blue to colourless(or white) : _________________
Ans: Copper sulphate crystals