determine avogadro's no if 1.8g of water contains 6.022×10^23 molecules
Answers
Answer:
But each molecule of water contains 2 H and 1 O atom = 3 atoms, so there are approximately 1.8 x 10^24 atoms in a mole of water.
Answer:
We get
1.81
×
10
24
water molecules...
Explanation:
We assess the molar quantity of water in the usual way...
Number of moles
=
mass
molar mass
≡
54
⋅
g
18.01
⋅
g
⋅
m
o
l
−
1
=
3.00
⋅
m
o
l
But the
m
o
l
is like the
dozen
, or the
gross
, it specifies a NUMBER, here
N
A
≡
6.022
×
10
23
⋅
m
o
l
. Why do we use such an absurdly large number? Because
N
A
⋅
1
H
⋅
atoms
have a MASS of
1
⋅
g
precisely...and thus the mole is the link between the micro world of atoms, and molecules, to the macro world of grams and litres....
And so (finally!) we take the product...
Number of water molecules
=
molar quantity
×
Avogadro's number.
=
3.00
⋅
m
o
l
×
6.022
×
10
23
⋅
m
o
l
−
1
a number as required..
=
?
?
⋅
water molecules