Question

c) sodium and oxygen.
d) magnesium and oxygen.
e) barium and chlorine.
f) calcium and nitrogen.
g) aluminum and sulfur.
h) calcium and fluorine.
i) aluminum and bromine.
j) lithium and phosphorus.

Explanation:

Step1: Analyze c) Sodium and oxygen

Sodium (Na) has a charge of +1, oxygen (O) has a charge of -2. To balance charges, we need 2 Na⁺ for 1 O²⁻. So the formula is $Na_2O$.

Step2: Analyze d) Magnesium and oxygen

Magnesium (Mg) has +2 charge, oxygen (O) has -2. So the formula is $MgO$ (1:1 ratio).

Step3: Analyze e) Barium and chlorine

Barium (Ba) has +2, chlorine (Cl) has -1. Need 2 Cl⁻ for 1 Ba²⁺. Formula: $BaCl_2$.

Step4: Analyze f) Calcium and nitrogen

Calcium (Ca) has +2, nitrogen (N) has -3. Find LCM of 2 and 3 (6). So 3 Ca²⁺ (total +6) and 2 N³⁻ (total -6). Formula: $Ca_3N_2$.

Step5: Analyze g) Aluminum and sulfur

Aluminum (Al) has +3, sulfur (S) has -2. LCM of 3 and 2 is 6. So 2 Al³⁺ (+6) and 3 S²⁻ (-6). Formula: $Al_2S_3$.

Step6: Analyze h) Calcium and fluorine

Calcium (Ca) +2, fluorine (F) -1. Need 2 F⁻ for 1 Ca²⁺. Formula: $CaF_2$.

Step7: Analyze i) Aluminum and bromine

Aluminum (Al) +3, bromine (Br) -1. Need 3 Br⁻ for 1 Al³⁺. Formula: $AlBr_3$.

Step8: Analyze j) Lithium and phosphorus

Lithium (Li) +1, phosphorus (P) -3. Need 3 Li⁺ for 1 P³⁻. Formula: $Li_3P$.

Answer:

c) $\boldsymbol{Na_2O}$
d) $\boldsymbol{MgO}$
e) $\boldsymbol{BaCl_2}$
f) $\boldsymbol{Ca_3N_2}$
g) $\boldsymbol{Al_2S_3}$
h) $\boldsymbol{CaF_2}$
i) $\boldsymbol{AlBr_3}$
j) $\boldsymbol{Li_3P}$