Chemistry/ grams to moles questions?

Question

I have three questions;

How many moles of atoms are in 10.81 grams of boron?

How many grams would 3 moles of boron weigh?

Ammonia molecules, NH3, have 1 nitrogen atom and 3 hydrogen atoms. How many grams would 1 mole of ammonia weigh?

Answer 1

The atomic mass of Boron (B) is 10.81 g/mol. Therefore, 10.81 grams will equal 1 mole. 3 moles will then equal 3 x 10.81 or 32.43 g.
The last is a little more in depth. Nitrogen has a mass of 14. Hydrogen has a mass of 1. A mole of ammonia would then have the total mass of three hydrogen and a nitrogen, or 17 g.

Answer 2

A mole is an animal and you can't get boron out of a mole------or can you ?

Answer 3

formula: mass x (mol/molar mass of molecule) a million. locate the molar mass of the molecule Al I3. So on your periodic table, locate Aluminum 26.982, and that i is 126.ninety one a million Al = 26.982 3 I = 3(126.ninety one) = 380.seventy 3 molar mass = a million Al + 3 I = 26.982 + 380.seventy 3 = 407.seventy one 2. Plug values into equation 15g of ALI3 x (a million mol / 407.seventy one g in line with ALI3 molecule) 3. resolve via utilising dimensional prognosis 15g of ALI3 x (a million mol / 407.seventy one g ALI3 ) = .0368 mols Your answer is .0368 mols