Question

part 3a 12 marks choose 4 of 5 (lesson 3a) draw the following ionic bonds and state the formula a) lithium and phosphorus b) calcium and chlorine c) magnesium and nitrogen d) aluminum and chlorine e) potassium and bromine

Explanation:

Step1: Determine charges of ions for lithium and phosphorus

Lithium (Li) is in Group 1, so it forms $Li^+$ with a +1 charge. Phosphorus (P) is in Group 15, it forms $P^{3 -}$ with a - 3 charge. To balance the charges, we need 3 Li⁺ ions for 1 $P^{3 -}$ ion. The formula is $Li_3P$.
To draw the ionic bond: Show 3 Li⁺ ions around 1 $P^{3 -}$ ion, with arrows indicating the transfer of electrons from Li atoms to P atom.

Step2: Determine charges of ions for calcium and chlorine

Calcium (Ca) is in Group 2, it forms $Ca^{2+}$ with a +2 charge. Chlorine (Cl) is in Group 17, it forms $Cl^-$ with a -1 charge. To balance the charges, we need 2 $Cl^-$ ions for 1 $Ca^{2+}$ ion. The formula is $CaCl_2$.
To draw the ionic bond: Show 1 $Ca^{2+}$ ion with 2 $Cl^-$ ions around it, with arrows indicating the transfer of 2 electrons from Ca atom to 2 Cl atoms.

Step3: Determine charges of ions for magnesium and nitrogen

Magnesium (Mg) is in Group 2, it forms $Mg^{2+}$ with a +2 charge. Nitrogen (N) is in Group 15, it forms $N^{3 -}$ with a - 3 charge. To balance the charges, we use the least - common multiple of 2 and 3. We need 3 $Mg^{2+}$ ions and 2 $N^{3 -}$ ions. The formula is $Mg_3N_2$.
To draw the ionic bond: Show 3 $Mg^{2+}$ ions and 2 $N^{3 -}$ ions, with arrows indicating the transfer of electrons from Mg atoms to N atoms.

Step4: Determine charges of ions for aluminum and chlorine

Aluminum (Al) is in Group 13, it forms $Al^{3+}$ with a +3 charge. Chlorine (Cl) is in Group 17, it forms $Cl^-$ with a -1 charge. To balance the charges, we need 3 $Cl^-$ ions for 1 $Al^{3+}$ ion. The formula is $AlCl_3$.
To draw the ionic bond: Show 1 $Al^{3+}$ ion with 3 $Cl^-$ ions around it, with arrows indicating the transfer of 3 electrons from Al atom to 3 Cl atoms.

Answer:

a) Formula: $Li_3P$; Ionic - bond drawing: 3 $Li^+$ around 1 $P^{3 -}$ with electron - transfer arrows.
b) Formula: $CaCl_2$; Ionic - bond drawing: 1 $Ca^{2+}$ with 2 $Cl^-$ around it and electron - transfer arrows.
c) Formula: $Mg_3N_2$; Ionic - bond drawing: 3 $Mg^{2+}$ and 2 $N^{3 -}$ with electron - transfer arrows.
d) Formula: $AlCl_3$; Ionic - bond drawing: 1 $Al^{3+}$ with 3 $Cl^-$ around it and electron - transfer arrows.