If it were determined that there were 6.391 x 10^22 atoms of H in an unknown sample of C2H4Cl2, how many milligrams would the unknown sample weigh?
Sorry for all the questions Dr. Bob.
So there are 6.391E22/4 molecules of C2H4Cl2. That divided by 6.022E23 = number of moles C2H4Cl2. Then moles x molar mass = grams. Convert to mg.
A sample of 0.43 moles of a metal M reacts completely with excess chlorine to form 18.23 grams of MCl.
How many moles of Cl are in the sample of MCl that forms?
No problem at all! I'm here to help. To determine the weight of the unknown sample, we need to first calculate the number of moles of C2H4Cl2 using the given information. Then, we can use the molar mass of C2H4Cl2 to convert moles to grams. Finally, we can convert grams to milligrams.
To calculate the moles of C2H4Cl2, we can use Avogadro's number (6.022 x 10^23 atoms/mole) and the given number of atoms of hydrogen (H) in the sample:
Number of moles = (Number of atoms of H) / Avogadro's number
Number of moles = (6.391 x 10^22 atoms of H) / (6.022 x 10^23 atoms/mole)
Now, we can determine the molar mass (grams/mole) of C2H4Cl2 by adding up the atomic masses of carbon (C), hydrogen (H), and chlorine (Cl) from the periodic table.
Molar mass of C2H4Cl2 = (2 x atomic mass of C) + (4 x atomic mass of H) + (2 x atomic mass of Cl)
Once you have the molar mass of C2H4Cl2, you can multiply the moles of C2H4Cl2 by the molar mass to obtain the mass in grams.
Mass (in grams) = Number of moles x Molar mass
Finally, to convert grams to milligrams, you can multiply the mass in grams by 1000.
Mass (in milligrams) = Mass (in grams) x 1000
By following these steps, you should be able to determine the weight of the unknown sample in milligrams.