The Language of Chemistry — CHEMISTRY STD 9 — Question

What is the achievement of Dobereiner’s law of triads?

Hydrogen may be prepared in the laboratory by the action of a metal on an acid.
How would you modify your apparatus to collect dry hydrogen? Which drying agent would you employ for this purpose?

From the knowledge of activity series, name a metal which shows the following properties:
It displaces hydrogen from hot water.

Name a metal which displaces hydrogen very slowly from dilute HCL.

How many electrons will weigh as much as one atom of hydrogen?

Does the mass and charge on positive rays remain same with the change in nature of gas in a discharge tube?

Define the term: Element

Give an example of double displacement reaction, where a gas is evolved.

Define
Crystallisation.