How many molecules of lithium carbonate are there in 8.62 g of the compound?
a) 74 molecules
b) 647 molecules
c) 0.12 molecules
d) 7.02x10^22 molecules
e) 1.42x10^-23 molecules
Well, let me put my clown nose on for this one!
To find out how many molecules of lithium carbonate are in 8.62 g, we need to start by calculating the molar mass of lithium carbonate.
The molar mass of lithium carbonate (Li2CO3) is calculated by adding up the atomic masses of each element in the compound. The atomic mass of lithium (Li) is 6.94 g/mol, carbon (C) is 12.01 g/mol, and oxygen (O) is 16.00 g/mol.
So, the molar mass of lithium carbonate is:
(2 * 6.94 g/mol) + 12.01 g/mol + (3 * 16.00 g/mol) = 73.89 g/mol
Now, we can use this molar mass to calculate the number of molecules in 8.62 g. To do this, we need to divide the mass of the compound by the molar mass and then multiply by Avogadro's number (6.022 x 10^23 molecules/mol).
Let's go clown mode on this equation:
Number of molecules = (8.62 g / 73.89 g/mol) * (6.022 x 10^23 molecules/mol)
After doing the math, we get approximately 7.02 x 10^22 molecules. So, the answer is (d) 7.02 x 10^22 molecules.
I hope that brought a smile to your face!
To find the number of molecules of lithium carbonate in 8.62 g of the compound, we need to use the concept of moles and Avogadro's number.
1. Calculate the molar mass of lithium carbonate (Li2CO3):
- Lithium (Li) has a molar mass of 6.94 g/mol.
- Carbon (C) has a molar mass of 12.01 g/mol.
- Oxygen (O) has a molar mass of 16.00 g/mol.
Molar mass of Li2CO3 = (2 * 6.94) + 12.01 + (3 * 16.00) = 73.89 g/mol
2. Use the molar mass to convert grams to moles:
Moles of Li2CO3 = (8.62 g) / (73.89 g/mol) = 0.1167 mol
3. Convert moles to molecules using Avogadro's number:
Avogadro's number, 6.022 x 10^23, represents the number of molecules in one mole of a substance.
Number of molecules = (0.1167 mol) * (6.022 x 10^23 molecules/mol)
Number of molecules = 7.02 x 10^22 molecules
Therefore, the correct answer is (d) 7.02 x 10^22 molecules.
To determine the number of molecules of lithium carbonate in a given mass of the compound, we need to use the concept of molar mass and Avogadro's number.
1. Calculate the molar mass of lithium carbonate (Li2CO3):
- The atomic mass of lithium (Li) is approximately 6.94 g/mol. Since there are two lithium atoms in the formula, the total contribution of lithium is 2 * 6.94 = 13.88 g/mol.
- The atomic mass of carbon (C) is approximately 12.01 g/mol.
- The atomic mass of oxygen (O) is approximately 16.00 g/mol. Since there are three oxygen atoms in the formula, the total contribution of oxygen is 3 * 16.00 = 48.00 g/mol.
- Adding up these contributions, the molar mass of lithium carbonate is 13.88 + 12.01 + 48.00 = 73.89 g/mol.
2. Use the molar mass to convert grams to moles:
- Divide the given mass of 8.62 g by the molar mass of 73.89 g/mol: 8.62 g / 73.89 g/mol = 0.1167 moles.
3. Apply Avogadro's number to convert moles to number of molecules:
- Avogadro's number is approximately 6.022 × 10^23 molecules/mol.
- Multiply the number of moles by Avogadro's number: 0.1167 moles * 6.022 × 10^23 molecules/mol = 7.02 × 10^22 molecules.
Therefore, the correct answer is (d) 7.02 × 10^22 molecules.
8.62 g Li2CO3 = how many moles.
mols = grama/molar mass
grams = 8.62
molar mass = 2*Li + C + 3*16 = 2*6.94 + 12.01 + 3*16 = 73.9
8.69/73.9 = 0.117 mols.
There are 6.02E23 molecules in 1 mol so......