Determine the mass(in grams) of each of the following compounds.
a) 0.709 mol magnesium fluoride
i got 30.7grams but it was wrong.
id appreciate the help! thanks!
also if i end up getting the help i have a couple other questions
nevermind i got the answer but i do have another question:
A salt crystal has a mass of 0.40 mg. How many NaCl formula units does it contain?
moles = grams/molar mass
Substitute "number formula units" for moles. Substitute "mass formula unit" for molar mass. Solve for moles.
0.04/about 58.5 or so. You do it more precisely.
so do i have to convert .4 mg to grams first? that would be .0004 right?
so then i just divide .004/58.44 and that will be my answer?
Yes, and I notice I didn't see the decimal point.
0.4 mg = 0.0004 grams and that divided by 58.44 = ?? formula units.
so it would be .000006845 formula units?
To determine the mass of a compound, you need to use its molar mass. The molar mass is the mass of one mole of a substance and is calculated by summing up the atomic masses of all the atoms present in the compound.
For magnesium fluoride (MgF2), you need to know the molar mass of magnesium (Mg) and fluorine (F). The atomic masses can be found on the periodic table.
Molar mass of Mg = 24.31 g/mol
Molar mass of F = 18.99 g/mol
To calculate the molar mass of magnesium fluoride (MgF2), multiply the atomic mass of magnesium by 1 (since there is one magnesium atom), and multiply the atomic mass of fluorine by 2 (since there are two fluorine atoms).
Molar mass of MgF2 = (24.31 g/mol * 1) + (18.99 g/mol * 2)
= 24.31 g/mol + 37.98 g/mol
= 62.29 g/mol
Now, to determine the mass of 0.709 mol of magnesium fluoride, you can use the formula:
Mass = Number of moles * Molar mass
Mass = 0.709 mol * 62.29 g/mol
≈ 44.13 grams
Therefore, the correct mass of 0.709 mol of magnesium fluoride is approximately 44.13 grams.
If you have any other questions, feel free to ask!