Question

Calculate the mass of fe(no3)3 that is measured to prepare 500.0 mL of a 0.175mol/L solution.​

Answer 1

21.3g

Step-by-step explanation:

The formula of the compound is;

Fe(NO₃)₃

Given:

volume = 500mL = 0.5L

concentration = 0.175mol/L

Unknown:

Mass of Fe(NO₃)₃ measured = ?

Solution:

To solve this problem, find the number of moles first;

Number of moles of Fe(NO₃)₃ = concentration x volume

So;

Number of moles = 0.175 x 0.5 = 0.088mol

Now to find the mass;

Mass = number of moles x molar mass

Molar mass of Fe(NO₃)₃ = 55.8 + 3[14 + 3(16)]

Molar mass of Fe(NO₃)₃ = 55.8 + 3(62) = 241.8g/mol

Mass = 0.088mol x 241.8g/mol = 21.3g