16. which of the following aqueous solutions contains the greatest number of 10ns.
a) 400.0 ml of 0.10 m nacl
b) 300.0 ml of 0.10 m cacl2
y 200.0 ml of 0.10 m fecl3
d) 200.0 ml of 0.10 m kb

Explanation:

a) 400.0 mL of 0.10 M NaCl

(i) Moles of NaCl

(ii) Moles of ions

NaCl(s) ⟶ Na⁺(aq) + Cl⁻(aq)

We get 2 mol of ions from 1 mol of NaCl

b) 300.0 mL of 0.10 M CaCl₂

(i) Moles of CaCl₂

(ii) Moles of ions

CaCl₂(s) ⟶ Ca²⁺(aq) + 2Cl⁻(aq)

We get 3 mol of ions from 1 mol of CaCl₂

c) 200.0 mL of 0.10 M FeCl₃  

(i) Moles of FeCl₃

(ii) Moles of ions

FeCl₂(s) ⟶Fe³⁺(aq) + 3Cl⁻(aq)

We get 4 mol of ions from 1 mol of  FeCl₃

d) 200.0 mL of 0.10 M KBr

(i) Moles of KBr

(ii) Moles of ions

KBr(s) ⟶ K⁺(aq) + Br⁻

We get 2 mol of ions from 1 mol of KBr

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6