Chem Calc

[Anonymous No.3014309]

The formula for rust can be represnted as Fe2O3. How many moles of Fe are present in 24.6 g of the compound?

Please show work and stuff, thanks

[Anonymous No.3014319]

What is the molar mass of Fe2O3, OP?
Use that to calculate how many moles of Fe2O3 there are.
The multiply that number by however many Fe atoms are in each Fe2O3 unit.

[Anonymous No.3014339]

Why do people keep trying to use /sci/ as the homework board?

At least >>3014319 is trying to get him to learn, but goddamn.

[Anonymous No.3014347]

The molar mass of Fe203 is 159.692. So then
24.6g Fe2O3 / 159.692g Fe2O3 = 0.151 mols Fe2O3

0.151 mols Fe2O3 x 2 mols Fe? The 2nd half doesn't make sense

[Anonymous No.3014351]

My chemistry is rusty so I just want to do this for fun.

Basically you divide by the molar mass of <span class="math">\displaystyle Fe2O_3[/spoiler] so you get moles and then multiply by the molar ratio (would that be 1:6 or 1:2?).

That way you have moles of Fe represented in <span class="math">\displaystyle Fe2O_3[/spoiler]. Then what?

[Anonymous No.3014368]

>>3014347
You have 0.151 mol Fe2O3 but each mol Fe2O3 has 2 mol Fe (since each Fe2O3 unit has 2 Fe atoms) so you have to multiply 0.151 mol by 2 to get 0.302 mol.

[Anonymous No.3014419]

Then what do you do with the 0.302 mols?

Btw this section is called Percent Calculation by Compostion. So it should be a little more complicated then basic n=m/M

[Anonymous No.3014444]

Bleh it was asking for moles of Fe. That's the end.

[Anonymous No.3014456]

>>3014419

.302 moles is your answer. I think many misunderstand what a "mole" is. It's analogous to "a dozen", such as a dozen atoms, or a mole of atoms.

[Anonymous No.3014651]

>>3014456

Thanks. Not OP here, but I have a senior chem class right now.

This is high school level shit, I knew it without even thinking too much. Seriously OP, get your shit together.