Question

A biochemist prepares a 1 L solution using 12.1 g of Tris Buffer. The final concentration is 0.1 M. What is the MW of Tris Buffer?

Answer 1

Answer: The molecular weight of tris buffer is 121 g/mol

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

$Molarity=\frac{n}{V_s}$

where,

n = moles of solute

$V_s$ = volume of solution in L

moles of tris buffer = $\frac{\text {given mass}}{\text {Molar mass}}=\frac{12.1g}{Mg/mol}$

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

$0.1=\frac{12.1g}{Mg/mol\times 1L}$

$M=121g/mol$

Therefore, the molecular weight of tris buffer is 121 g/mol