Question

which of the following equations is balanced?
a. na₂so₄(aq) + cacl₂(aq) → caso₄(s) + nacl(aq)
b. na₂so₄(aq) + cacl₂(aq) → caso₄(s) + 2nacl(aq)
c. 2na₂so₄(aq) + cacl₂(aq) → caso₄(s) + 2nacl(aq)
d. na₂so₄(aq) + 2cacl₂(aq) → caso₄(s) + nacl(aq)

Explanation:

Step1: Check option A

On the left - hand side, there are 2 Na, 1 S, 4 O, 1 Ca, and 2 Cl. On the right - hand side, there are 1 Na, 1 S, 4 O, 1 Ca, and 1 Cl. The number of Na and Cl atoms is not balanced.

Step2: Check option B

On the left - hand side:

• Na: 2 from \(Na_2SO_4\)
• S: 1 from \(Na_2SO_4\)
• O: 4 from \(Na_2SO_4\)
• Ca: 1 from \(CaCl_2\)
• Cl: 2 from \(CaCl_2\)

On the right - hand side:

• Na: \(2\times1 = 2\) from \(2NaCl\)
• S: 1 from \(CaSO_4\)
• O: 4 from \(CaSO_4\)
• Ca: 1 from \(CaSO_4\)
• Cl: \(2\times1=2\) from \(2NaCl\)

The equation is balanced.

Step3: Check option C

On the left - hand side, there are 4 Na, 2 S, 8 O, 1 Ca, and 2 Cl. On the right - hand side, there are 2 Na, 1 S, 4 O, 1 Ca, and 2 Cl. The number of Na, S, and O atoms is not balanced.

Step4: Check option D

On the left - hand side, there are 2 Na, 1 S, 4 O, 2 Ca, and 4 Cl. On the right - hand side, there are 1 Na, 1 S, 4 O, 1 Ca, and 1 Cl. The number of Na, Ca, and Cl atoms is not balanced.

Answer:

B. \(Na_2SO_4(aq)+CaCl_2(aq)
ightarrow CaSO_4(s) + 2NaCl(aq)\)