Advertisements
Advertisements
Question
(a) Write the symbols/formulae of two simple ions and two compound ions (or polyatomic ions).
Advertisements
Solution
(a) Example of a simple ion: Iodine atom forms an iodide ion by accepting an electron, I-. Similarly, magnesium loses two electrons to form a magnesium ion, Mg2+.
Example of a compound ion: Carbonate ion, CO32-, is made up of two types of atoms i.e. carbon and oxygen (chemically bonded). Similarly, ammonium ion, NH4+, is made up of two types of atoms i.e. nitrogen and hydrogen (chemically bonded).
APPEARS IN
RELATED QUESTIONS
What is meant by the term chemical formula?
The radius of an oxygen atom is 0.073 nm. What does the symbol ‘nm’ represent ?
What is meant by a chemical formula ? Write the formulae of one element and one compound.
The formula of a compound is X3Y. The valencies of elements X and Y will be respectively :
The formula of carbonate of a metal M is M2CO3.
What will be the formula of its phosphate ?
Give the empirical formula of : Benzene C6H6
Define the term Relative molecular mass. State why indirect methods are utilised to determine the absolute mass of an atom. Explain in brief the indirect method used.
State of the following formula of a compound is incorrect. Incorrectly write the correct formula.
(NH4)3SO4
Play a game for writing formula.
Example 2: A low-cost model for writing formulae: Take empty blister packs of medicines. Cut them in groups according to the valency of the element, as shown in the figure. Now, you can make formulae by fixing one type of ion into other.
For example:

The formula for sodium sulphate:
2 sodium ions can be fixed on one sulphate ion.
Hence, the formula will be Na2SO4.
Do it yourself:
Now, write the formula of sodium phosphate.
