Archana Shukla Solutions for Chapter: Elements, Compounds and Chemical Equations, Exercise 10: EVALUATE

Name the element denoted by the symbol $\mathrm{F}\mathrm{e}$. (Francium / Iron)

The polyatomic molecule of an element with atomic number $15$ is ${\mathrm{P}}_{\mathrm{n}}$. here, the value of $\mathrm{n}$ is 

Write the chemical formulae of the following compound:
Potassium carbonate

Name the compounds formed by sodium. Also, write their chemical formulae.

Explain the physical method by which salt can be separated from salty water.

If the valency of calcium is $2$, derive the valencies of the other elements or radicals present in the following compounds: Calcium chloride $\left({\mathrm{C}\mathrm{a}\mathrm{C}\mathrm{l}}_2\right)$, Calcium hydroxide $\left(\mathrm{C}\mathrm{a}{\left(\mathrm{O}\mathrm{H}\right)}_2\right)$, Calcium phosphate $\left({\mathrm{C}\mathrm{a}}_3{\left(\mathrm{P}{\mathrm{O}}_4\right)}_2\right)$.

When a dish containing ink is heated, we would observe evaporation is taking place. The dish heated continuously till no further change is seen and only dye is left behind. Was the original substance, i.e. ink an element, compound or mixture?

A balanced chemical equation for the reaction between sodium bicarbonate and hydrochloric acid is: