Answer :

Answer:

[tex]0.36\text{ mole}[/tex]

Explanation:

Here, we want to get the number of moles contained

To get this, we have to multiply the volume in L by the molarity

Mathematically, we have that as:

[tex]moles\text{ = volume * molarity}[/tex]

We have this as:

[tex]moles\text{ = }\frac{400}{1000}\text{ }\times\text{ 0.90 = 0.36 mole}[/tex]