What is the molarity and molality of a solution prepared by mixing 23g of cacl2 with 217g of water(assuming density of water is 1g/mol)

Molarity = 0.9 M

Molality = 0.95 m

Explanation:

Data given:

mass of CaCl₂ = 23 g

mass of water = 217g

Density of water = 1g/mol

molality of solution = ?

molarity of solution = ?

Solution:

Molarity and Molality are terms used for concenteration of solution

Formula Used for Molarity

                    Molarity = moles of solute / liter of solution . . . . . (1)

So first we find number of moles of 23 g CaCl₂.

Formula used to find moles

                no. of moles = mass in g / molar mass

molar mass CaCl₂ = 40 + 2(35.5)

molar mass CaCl₂ = 40 + 71 = 111 g/ mole

So,

Put values in mole formula

                  no. of moles = 23 g / 111 g/mol

                   no. of moles = 0.21 mol

Now,

As for molarity we have to convert grams of water to liter

for this purpose we will use density formula

                      d= m/v

for volume rearrange the above equation

                     v = m/d . . . . . . . (2)

put vlue in above equation 2

                  v = 217 g / 1 (g/mL)

                    v = 217 mL

Now,

Total amount of solution = 23 + 217 = 240 mL

Now, Convert the mL to Liter

1000 = 1 L

240 mL = 240 /1000 = 0.24 L

So no we have the following required values to find molarity

no. of moles of CaCl₂ = 0.21 mol

liter of solution = 0.24 L

Put values in equation 1

                 Molarity = 0.21 mol / 0.24 L

                 Molarity = 0.9 M

To find Molality (m)

Formula used to find Molality

                 Molality = moles of solute / kg of solvent . . . . . . . (3)

So, no we have to convert grams of water to Kg

1000 g = 1 kg

217 g = 217 / 1000 = 0.22 Kg

Now,

Put values in equation

                 Molality = 0.21 mol / 0.22 kg

                 Molality = 0.95 m

So, the Molality =  0.95 m

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation: