How many oxygen atoms do you have in 2.00 grams of calcium phosphate?
My answer is 3.9*10^22 by multiplying avogadros number by (2/31)
Am I close?
How many Ca^2+ ions do you have in 2.00 grams of calcium phosphate?
I am getting 39, am i close? since there are 3 Ca2+ ions per molecule,I just multiplied that by 13.
3,9 x 10^22 is close but not close enough. I used 310.177 for the molar mass. For Ca, multiplying by 13 won't get it. Multiply # moles by 3.
DrWLS gave instructions to you how to solve this problem much much earlier in the day. (But the number of moles is 2/310.177 and not 2/31.)
To determine the number of oxygen atoms in 2.00 grams of calcium phosphate, we need to follow a few steps:
Step 1: Calculate the molar mass of calcium phosphate.
The molar mass of calcium phosphate (Ca3(PO4)2) can be calculated by summing the atomic masses of its constituent elements:
Ca: 40.08 g/mol (atomic mass of calcium)
P: 30.97 g/mol (atomic mass of phosphorus)
O: 16.00 g/mol (atomic mass of oxygen)
The molar mass of calcium phosphate = (3 * 40.08) + (2 * 30.97) + (8 * 16.00) g/mol
= 310.18 g/mol
Step 2: Calculate the number of moles of calcium phosphate.
To convert grams to moles, use the formula: moles = mass / molar mass.
moles of calcium phosphate = 2.00 g / 310.18 g/mol
≈ 0.00645 mol
Step 3: Calculate the number of oxygen atoms.
In one molecule of calcium phosphate (Ca3(PO4)2), there are 8 oxygen atoms.
number of oxygen atoms = (0.00645 mol) * (6.022 x 10^23 atoms/mol) * (8 atoms)
≈ 3.90 x 10^21 oxygen atoms
Therefore, the correct answer is approximately 3.90 x 10^21 oxygen atoms, and not 3.9 x 10^22.
Now, let's determine the number of Ca^2+ ions.
Step 1: Calculate the number of moles of Ca^2+ ions.
In one molecule of calcium phosphate (Ca3(PO4)2), there are 3 Ca^2+ ions.
moles of Ca^2+ ions = 0.00645 mol * 3
= 0.01935 mol
Step 2: Calculate the number of Ca^2+ ions.
In one mole of any substance, there are 6.022 x 10^23 entities.
number of Ca^2+ ions = 0.01935 mol * (6.022 x 10^23 ions/mol)
≈ 1.17 x 10^22 Ca^2+ ions
Therefore, the correct answer is approximately 1.17 x 10^22 Ca^2+ ions, and not 39.