What is the concentration, in mol L-1, of a solution containing 1.2 g of lithium carbonate in 100 mL solution?
Give your answer as 2 sig fig, followed by a space and the units (remember the units given in a previous question).
mols Li2CO3 = grams/molar mass
M = mols/0.1L = ?
how do i find molar mass?
To find the concentration in mol L-1, we need to convert the mass of lithium carbonate to moles and then divide by the volume of the solution in liters.
1. Convert the mass of lithium carbonate (1.2 g) to moles:
- The molar mass of lithium carbonate (Li2CO3) is:
- 2 x atomic mass of Li + atomic mass of C + 3 x atomic mass of O
- 2 x 6.94 g/mol + 12.01 g/mol + 3 x 16.00 g/mol
- 73.89 g/mol
- To convert grams to moles, divide the mass by the molar mass:
- 1.2 g / 73.89 g/mol = 0.0162 mol
2. Convert the volume of the solution (100 mL) to liters:
- Divide the volume by 1000 to convert from milliliters to liters:
- 100 mL / 1000 = 0.1 L
3. Finally, calculate the concentration:
- Divide the number of moles by the volume in liters:
- 0.0162 mol / 0.1 L = 0.162 mol L-1
To follow the significant figures rule in this question, round the concentration to two significant figures.
Therefore, the concentration of the solution containing 1.2 g of lithium carbonate in 100 mL solution is 0.16 mol L-1.