Question

(8) Iron (III) sulphate
(h) Nitric acid
(i) Calcium phosphate
(j) Aluminium sulphate
(k) Magnesium nitride
write molecular formula​

Answer 1

1. iron = fe
2. sulphate = So4
3. calcium phosphate = Ca3(Ph4)2
4. nitric acid = HNO3
5. Aluminum sulphate = AL2(SO4)3
6. Magnesium nitrade = Mg(NO3)2

Answer 2

AnswEr:

1). Molecular formula of Iron (iii) Sulphate

→ $\red{\sf{Fe_{2} (SO_{4})_{3}}}$

2). Molecular formula of Nitric acid

→ $\green{\sf{HNO_{3}}}$

3). Molecular formula of Calcium phosphate

→ $\blue{\sf{Ca_{3} (PO_{4})_{2}}}$

4). Molecular formula of Aluminum Sulphate

→ $\pink{\sf{Al_{2} (SO_{4})_{3}}}$

5). Molecular formula of Magnesium nitride

→ $\purple{\sf{Mg_{3} N_{2}}}$

$\rule{200}2$

What is chemical formula?

→ The symbolic representation of a compound is called a chemical formula.

How to make it?

Let's take an example,

Chemical formation of Calcium chloride :

Step 1 : Write the symbols and atomic number of elements separately.

→ Ca ( Atomic number 20 ) - Cl ( Atomic number 17 )

Step 2 : Write its electronic configuration.

→ Ca ( 2,8,8,2 ) - Cl ( 2,8,7 )

Step 3 : Find out its valency using valence electrons.

→ $\sf{Ca^{2+}}$ - $\sf{Cl^{1-}}$

Step 4 : Crossing both, we get the chemical formula or molecular formula.

→ $\sf{\red{CaCl_{2}}}$