Question

Silver nitrate reacts with calcium chloride as

shown.
2 AgNO3 + CaCl2 → 2 AgCl + Ca(NO3)2

How many grams of CaCl2 would be required to completely react with 420 mL of
0.506 M AgNO3 solution?
Answer in units of grams.

Answer 1

To find the grams of CaCl2 required to react with a given amount of AgNO3 solution, we can use the stoichiometry of the balanced equation. By calculating the moles of AgNO3 and then using the mole ratio, we can determine the moles of CaCl2 required. Finally, by multiplying the moles of CaCl2 by its molar mass, we can find the grams of CaCl2 required.

Step-by-step explanation:

To calculate the grams of CaCl2 required to completely react with the given amount of AgNO3 solution, we need to use the balanced equation and stoichiometry. From the balanced equation:

2 AgNO3 + CaCl2 → 2 AgCl + Ca(NO3)2

We can see that the ratio of CaCl2 to AgNO3 is 1:2. Given that the AgNO3 solution has a concentration of 0.506 M, we can calculate the moles of AgNO3 using the formula:Moles = concentration × volume

Substituting the given values:Moles of AgNO3 = 0.506 M × 0.420 L = 0.21252 moles

Since the ratio of CaCl2 to AgNO3 is 1:2, the moles of CaCl2 required would be half of the moles of AgNO3, which is:Moles of CaCl2 = 0.21252 moles ÷ 2 = 0.10626 moles

To convert moles of CaCl2 to grams, we need to multiply by its molar mass. The molar mass of CaCl2 is:Molar mass of CaCl2 = 40.08 g/mol + 2(35.45 g/mol) = 110.98 g/mol

Therefore, the grams of CaCl2 required is:Grams of CaCl2 = 0.10626 moles × 110.98 g/mol = 11.8 grams

Answer 2

Answer: 11.8 grams of
`CaCl_2` is required.

Step-by-step explanation:

To calculate the number of moles for given molarity, we use the equation:

`\text{Molarity of the solution}=\frac{\text{Moles of solute}* 1000}{\text{Volume of solution (in L)}}` .....(1)

Molarity of
`AgNO_3` solution = 0.506 M

Volume of solution = 420 mL

Putting values in equation 1, we get:

`0.506M=\frac{\text{Moles of} AgNO_3* 1000}{420ml}\\\\\text{Moles of }AgNO_3=(0.506mol/L* 420)/(1000)=0.212mol`

The balanced chemical reaction is:

`2AgNO_3+CaCl_2\rightarrow 2AgCl+Ca(NO_3)_2`

2 mole of
`AgNO_3` requires = 1 mole of
`CaCl_2`

0.212 moles of
`AgNO_3` require =
`(1)/(2)* 0.212=0.106` moles of
`CaCl_2`

Mass of
`CaCl_2` =
`moles* {\text {Molar Mass}}=0.106mol* 111g/mol=11.8g`