Question

when dissolved in water one unit of calcium chloride produces ___ ions.
1
2
0
3
question 2
10 pts
which one of the following compounds is soluble in water?
magnesium carbonate
zinc hydroxide
barium sulfate
sodium carbonate

Explanation:

Question 1 (Calcium Chloride Dissociation)

Step1: Recall the formula of calcium chloride

Calcium chloride has the formula $CaCl_2$.

Step2: Determine dissociation in water

When $CaCl_2$ dissolves in water, it dissociates as $CaCl_2
ightarrow Ca^{2+} + 2Cl^-$. So one unit of $CaCl_2$ produces 1 $Ca^{2+}$ ion and 2 $Cl^-$ ions, totaling $1 + 2 = 3$ ions.

• Magnesium carbonate ($MgCO_3$): Carbonates of most metals (except Group 1, ammonium) are insoluble. Magnesium is not Group 1, so $MgCO_3$ is insoluble.
• Zinc hydroxide ($Zn(OH)_2$): Hydroxides of most metals (except Group 1, ammonium, some Group 2) are insoluble. Zinc is not in those exceptions, so $Zn(OH)_2$ is insoluble.
• Barium sulfate ($BaSO_4$): Sulfates of barium, lead, calcium (slightly) are insoluble. So $BaSO_4$ is insoluble.
• Sodium carbonate ($Na_2CO_3$): Carbonates of Group 1 metals (like sodium) are soluble in water.

Answer:

3 (corresponding to the option "3")

Question 2 (Solubility of Compounds)