Mixing solutions of iron(III) nitrate and sodium hydroxide precipitates the pigment iron(III) hydroxide. What mass of iron(III)
hydroxide is produced from 24.1 grams of sodium hydroxide?
Type the correct answer in the box. Express your answer to the correct number of significant figures C. Use the
periodic table to obtain the atomic masses of the elements.
The reaction will produce ___
grams of iron(III) hydroxide.

21.5

Explanation:The reactants are sodium hydroxide and iron(III) nitrate. From the periodic table, determine that the molar mass of NaOH is 39.997 grams/mole and the molar mass of Fe(OH)3 is 106.866 grams/mole.

This is a double displacement reaction that produces iron(III) hydroxide and sodium nitrate.

This is the balanced equation:

Fe(NO3)3 + 3NaOH → Fe(OH)3 + 3NaNO3.

The equation shows that for every three moles of NaOH, one mole of Fe(OH)3 is produced. So, there are three times as many moles of NaOH used up as there are moles of Fe(OH)3 produced.

Find the number of moles of NaCl and divide by 3 to get the moles of Fe(OH)3 produced:

24.1 g NaOH ×  = 0.603 mol NaOH

0.603 mol NaOH ×  = 0.201 mol Fe(OH)3

Multiply the number of moles of Fe(OH)3 by its molar mass to get the number of grams of Fe(OH)3 produced:

0.201 mol Fe(OH)3 × 106.866 g/mol Fe(OH)3 = 21.5 g Fe(OH)3

The answer is rounded to three significant figures.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3