How many molecules are contained in a 7.60-g sample of dimethylmercury?
mols = grams/molar mass = ?
Then, a mole contains 6.02E23 molecules.
((C H 3) 2 Hg)
2 C = 2 * 12 = 24 g/mol
6 H = 6 g/mol
2 Hg = 2*200.6 = 401 g/mol
sum = 431 grams / mol
so Avagadro's number * 7.6 /431
why 2Hg?
Whoops, typo, thanks, 1 Hg
To determine the number of molecules in a sample of a substance, we need to use the concept of moles and Avogadro's number.
First, we need to calculate the number of moles of dimethylmercury in the 7.60 g sample. To do this, we need to know the molar mass of dimethylmercury, which can be found by adding the atomic masses of its constituent elements.
The molecular formula of dimethylmercury is CH3HgCH3. The atomic masses of carbon (C), hydrogen (H), and mercury (Hg) are approximately 12.01 g/mol, 1.01 g/mol, and 200.59 g/mol, respectively.
The molar mass of dimethylmercury can be calculated as follows:
Molar mass of CH3HgCH3 = (12.01 g/mol * 2) + (1.01 g/mol * 6) + (200.59 g/mol) = 230.77 g/mol
Now we can calculate the number of moles of dimethylmercury in the sample:
Number of moles = Mass of sample / Molar mass
Number of moles = 7.60 g / 230.77 g/mol
Once we have the number of moles, we can use Avogadro's number to convert moles to the number of molecules:
Avogadro's number = 6.022 × 10^23 molecules/mol
Number of molecules = Number of moles * Avogadro's number
By substituting the calculated value of moles and Avogadro's number, we can find the number of molecules in the 7.60 g sample of dimethylmercury.