62,243 views
8 votes
8 votes
Calcium Carbonate (CaCO3) or calcite, is the mineral found in limestone, marble, chalk, pearls, and marine animal shells. a) Calculate the molar mass of calcium carbonate?b) What is the mass of 18.18 moles of a sample of Calcium carbonate in kg?c) What is the mass of the carbonate ions (CO3^2-) in 18.18 g of calcium carbonate?

User SirRichie
by
2.2k points

1 Answer

9 votes
9 votes

a) Molar mass of Calcium Carbonate:

CaCO3

Molar mass of:

Ca - 40 g/mol

C - 12 g/mol

O - 16 g/mol

We need to multiply the molar mass of each atom by the quantity of this element in the molecular formula, and then sum the results:

(1*40) + (1*12) + (3*16) = 100 g/mol

Answer a): 100 g/mol

b) To find the mass of 18.18 moles of a sample of CaCO3, we need to use the following formula: mass = moles * molar mass

mass = 18.18 * 100

mass = 1,818 g of CaCO3

We need to transform to Kg, so we just divide the result by 1000:

1.818 Kg

Answer b): 1.818 Kg of CaCO3

c) First, let's write the equation of dissociation of CaCO3:

CaCO3 -> Ca^2+ + CO3^2-

So 1 mol of CaCO3 produces 1 mol of CO3^2-

Now let's transform 18.18 g of CaCO3 into moles using the following formula: moles = mass/molar mass

moles = 18.18/100

moles = 0.1818

As we find before, 1 mole of CaCO3 produces 1 mole of CO3^2-

So 0.1818 moles of CaCO3 produces 0.1818 moles co CO3^2-

Let's find the mass of CO3^2- using the following formula:

mass = moles x molar mass

molar mass of CO3^2- = 60 g/mol

mass = 0.1818 x 60

mass = 10.908 g

Answer c): 10.908 g

User Alessioalex
by
2.5k points