<u>Answer:</u> The expression of 
is written below.
<u>Explanation:</u>
We are given a chemical compound which is trimethylamine that acts as a weak base when dissolved in water.
It accepts a proton from the water to form trimethylammonium ion and hydroxide ion.
The chemical equation for the reaction of trimethylamine in water follows:
The expression of for above equation follows:
![K_b=\frac{[(CH_3)_3NH^+][OH^-]}{[(CH_3)_3N]}](https://tex.z-dn.net/?f=K_b%3D%5Cfrac%7B%5B%28CH_3%29_3NH%5E%2B%5D%5BOH%5E-%5D%7D%7B%5B%28CH_3%29_3N%5D%7D)
Hence, the expression of is written above.
<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We do as follows:
4.50 mol Fe ( 6.022x10^23 atoms / 1 mol Fe ) = 2.71x10^24 atoms Fe present </span>
The density of an object ρ = 24 g/ml
<h3>Further explanation</h3>
Given
mass of an object = 120 g
volume = 5 ml
Required
The density
Solution
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:
ρ = density
m = mass
v = volume
Input the value :
ρ = 120 g : 5 ml
ρ = 24 g/ml
