Answer:
0.967mole
Explanation:
Given parameters:
Volume of NH₄Cl = 21.67L
Unknown:
Number of moles = ?
Solution:
We assume that the volume was taken at standard temperature and pressure,
Then;
Number of moles =
Number of moles = = 0.967mole
Answer:
Density of the He atom = 12.69 g/cm³
Explanation:
From the information given:
Since 1 mole of an atom = 6.022x 10²³ atoms)
1 atom of He =
The volume can be determined as folows:
since the diameter of the He atom is approximately 0.10 nm
the radius of the He = = 0.05 nm
Converting it into cm, we have:
Assuming that it is a sphere, the volume of a sphere is
=
=
=
Finally, the density can be calcuated by using the formula :
D = 12.69 g/cm³
Density of the He atom = 12.69 g/cm³