How many grams of silver chromate are produced when 250. mL of 1.500 M Na2CrO4 are added to excess silver nitrate? Please balance the equation before solving the problem.

1 Answer
May 31, 2018

Answer:

The mass of #"Ag"_2"CrO"_4# produced is 124 g.

Explanation:

There are four steps involved in this stoichiometry problem:

  1. Write the balanced chemical equation
  2. Calculate the moles of #"Na"_2"CrO"_4#
  3. Use the molar ratio from the balanced equation to calculate the moles of #"Ag"_2"CrO"_4#
  4. Calculate the mass of #"Ag"_2"CrO"_4#

Step 1. Write the balanced chemical equation.

#M_r:color(white)(mmmmmmmmmmmmmll) 331.73#
#color(white)(mmm)"2AgNO"_3 + "Na"_2"CrO"_4 →"Ag"_2"CrO"_4 + "2NaNO"_3#

Step 2. Calculate the moles of #"Na"_2"CrO"_4#

#"Moles of Na"_2"CrO"_4 = 0.250 color(red)(cancel(color(black)("L Na"_2"CrO"_4))) × ("1.500 mol Na"_2"CrO"_4)/(1 color(red)(cancel(color(black)("L Na"_2"CrO"_4)))) = "0.3750 mol Na"_2"CrO"_4#

Step 3. Calculate the moles of #"Ag"_2"CrO"_4#

The molar ratio from the balanced equation is

#"Ag"_2"CrO"_4:"Na"_2"CrO"_4 = 1:1#.

#"Moles of Ag"_2"CrO"_4 = 03750 color(red)(cancel(color(black)("mol Na"_2"CrO"_4))) × ("1 mol Ag"_2"CrO"_4)/(1 color(red)(cancel(color(black)("mol Na"_2"CrO"_4)))) = "0.3750 mol Ag"_2"CrO"_4#

Step 4. Calculate the mass of #"Ag"_2"CrO"_4#

#"Mass of Ag"_2"CrO"_4 = 0.3750 color(red)(cancel(color(black)("mol Ag"_2"CrO"_4))) × ("331.73 g Ag"_2"CrO"_4)/(1color(red)(cancel(color(black)("mol Ag"_2"CrO"_4)))) = "124 g Ag"_2"CrO"_4#