Explanation:
It is given that r = 0.283 nm. As 1 nm =
.
Hence, 0.283 nm = 
- Formula for coulombic energy is as follows.

where, e =
C
= 

= 
- As 1 eV =

So, 1 J = 
Hence, U = 
= 8.9 eV
- Also, 1 J =

=
kJ/mol
Therefore, U =
kJ/mol
= 
At stp the volume is 22.4 L .
hope this helps!
Given:
Atomic radius of gold = 144 x 10⁻¹² m = 144 pm
Density of gold = 19.3 g/cm³ = 19.3 x 10⁻³ kg/cm³
Mass of gold sample = 1.40 g = 1.4 x 10⁻³ kg
Calculate the volume of an atom.
v = [(4π)/3]*(144 x 10⁻¹² m)³ = 1.2508 x 10⁻²⁹ m³
Calculate the mass of an atom.

Calculate the number of atoms in a sample of mass 1.40 g.

Answer: 5.8 x 10²¹ atoms
Explanation:
Kẽm tác dụng với axit clorua ( nhiệt độ ) thì sẽ tạo ra Kẽm II clorua và có khí Hidro bay lên