You have 218.0 g of potassium carbonate.

How many moles of potassium carbonate do you have?

How many potassium atoms are there?

Draw a Lewis structure of carbonate. Is the anion carbonate stable?

Question

You have 218.0 g of potassium carbonate.

How many moles of potassium carbonate do you have?

How many potassium atoms are there?

Draw a Lewis structure of carbonate. Is the anion carbonate stable?

| General Chemistry 1

Accepted Answer

Potassium carbonate = K₂CO₃

n (K₂CO₃) = $\frac{m (K_{2} {CO}_{3})}{M (K_{2} {CO}_{3})}$

M(K₂CO₃) = 2 M(K) + M(C) + 3M(O) = 138.21 g.mol^-1

⇒ n (K₂CO₃) = $\frac{218.0}{138.21}$ = 1.577 mol

Number of K = N(K) = 2 x N(K₂CO₃) = n (K₂CO₃) x N_A = 1.577 x 6.022 x 10²³ = 9.467 x 10²³atoms.

The anion carbonate is stable because it has 3 different resonance forms ⇒ stabilization by resonance

Final - Question 10 | General Chemistry 1