How many moles of solute are contained in a 250.0 ml solution with a concentration of 2.5 m

 0.625 moles of solute are contained in a 250.0 ml solution with a concentration of 2.5 M

Explanation:

Molarity : It is defined as the number of moles of solute present per liter of the solution.

Formula used :

where,

n= moles of solute  = ?

= volume of solution in ml = 250 ml

Now put all the given values in the formula of molarity, we get

Therefore, the moles of solute will be 0.625.

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.