Question

boron carbonate decomposes into boron oxide and carbon dioxide. how many moles of co2 are produced when 5.0 mol of boron carbonate decomposes completely? (1 point) enter your answer 7 which is the correct mole ratio of k3po4 to kno3 in the chemical reaction: (0.5 points) mg(no3)2 + k3po4 →mg3(po4)2 + kno3? 1:3 2:3 1:2 1:1

Explanation:

First Question (Boron Carbonate Decomposition)

Step1: Write the balanced equation

The formula for boron carbonate is \( B_2(CO_3)_3 \), boron oxide is \( B_2O_3 \), and carbon dioxide is \( CO_2 \). The decomposition reaction is:
\( B_2(CO_3)_3
ightarrow B_2O_3 + 3CO_2 \) (balanced by ensuring C and O are balanced: 3 \( CO_2 \) from 3 \( CO_3^{2-} \) groups).

Step2: Determine mole ratio

From the balanced equation, 1 mol of \( B_2(CO_3)_3 \) produces 3 mol of \( CO_2 \).

Step3: Calculate moles of \( CO_2 \)

Given 5.0 mol of \( B_2(CO_3)_3 \), use the ratio:
Moles of \( CO_2 = 5.0 \, \text{mol} \times \frac{3 \, \text{mol} \, CO_2}{1 \, \text{mol} \, B_2(CO_3)_3} = 15 \, \text{mol} \).

Step1: Balance the chemical equation

The unbalanced equation is:
\( Mg(NO_3)_2 + K_3PO_4
ightarrow Mg_3(PO_4)_2 + KNO_3 \)

• Balance Mg: 3 \( Mg(NO_3)_2 \) (since product has 3 Mg).
• Balance \( PO_4^{3-} \): 2 \( K_3PO_4 \) (since product has 2 \( PO_4^{3-} \)).
• Balance \( NO_3^- \): 6 \( KNO_3 \) (from 3 \( Mg(NO_3)_2 \), which has 6 \( NO_3^- \)).
• Balance K: 2 \( K_3PO_4 \) gives 6 K, which matches 6 \( KNO_3 \).

Balanced equation:
\( 3Mg(NO_3)_2 + 2K_3PO_4
ightarrow Mg_3(PO_4)_2 + 6KNO_3 \)

Step2: Find mole ratio of \( K_3PO_4 \) to \( KNO_3 \)

From the balanced equation, 2 mol of \( K_3PO_4 \) produces 6 mol of \( KNO_3 \). Simplify the ratio:
\( \frac{\text{Moles of } K_3PO_4}{\text{Moles of } KNO_3} = \frac{2}{6} = \frac{1}{3} \), so the ratio is \( 1:3 \).

Answer:

15

Seventh Question (Mole Ratio of \( K_3PO_4 \) to \( KNO_3 \))