Answer:
Explanation:
To convert from molecules to moles, we must Avogadro's Number.
This number is how many particles (atoms, molecules, ions, etc.) in 1 mole of a substance. In this case, it is molecules of ammonia in 1 mole of ammonia.
Use Avogadro's number as a ratio.
Multiply by the given number of ammonia molecules (6.21*10²⁴)
Flip the fraction so the molecules of ammonia can cancel out.
Multiply to make 1 fraction.
Divide.
The original measurement of molecules had 3 significant figures (6,2 and 1). Therefore we must round our answer to 3 sig figs.
For the answer we found, 3 sig figs is the tenth place. The 1 in the hundredth place tells us to leave the 3 in the tenth place.
There are about <u>10.3 moles of ammonia</u> in 6.21*10²⁴ molecules.
Answer:
1.63ₓ10⁻⁶ g of U
139.03 g of H
0.385 g of O
141.8 g of Pb
Explanation:
In first place, we need to convert the number of atoms to moles, as we know that 1 mol of anything occupies 6.02×10²³ particles
Therefore:
4.12×10¹⁵ atoms of U . 1 mol / 6.02×10²³ atoms = 6.84×10⁻⁹ moles of U
8.37×10²⁵ atoms of H . 1 mol /6.02×10²³ atoms = 139.03 moles of H
1.45×10²² atoms of O . 1 mol /6.02×10²³ atoms = 0.0241 moles of O
4.12×10²³ atoms of Pb . 1 mol /6.02×10²³ atoms = 0.684 moles of Pb
Moles . Molar mass = Mass (g)
6.84×10⁻⁹ moles of U . 238.03 g/mol = 1.63ₓ10⁻⁶ g of U
139.03 moles of H . 1 g/mol = 139.03 g of H
0.0241 moles of O . 16 g/mol = 0.385 g of O
0.684 moles of Pb . 207.2 g/mol = 141.8 g of Pb
Covalent bonds... hope this helpss :)
Approx.
15
⋅
g
of metal.
Explanation:
Moles of iron oxide,
F
e
2
O
3
=
21.6
⋅
g
159.69
⋅
g
⋅
m
o
l
=
0.135
⋅
m
o
l
with respect to the oxide.
But by the composition of the oxide, there are thus
2
×
0.135
⋅
m
o
l
×
55.8
⋅
g
⋅
m
o
l
−
1
iron metal
=
?
?
g
.
An extraordinary percentage of our budgets goes into rust prevention;
iron(III) oxide
is only part of the redox chemistry. Once you put up a bridge or a skyscraper, which is inevitably steel-based structure, it will begin to corrode.