Use 25.4 g/ 425ml x 100 5.94 percent
Molar mass KCl = 74.55 g/mol
Number of moles:
mass KC / molar mass
149 / 74.55 => 1.998 moles
Volume in liters: 500 mL / 1000 => 0.5 L
Therefore:
M = moles / volume
M = 1.998 / 0.5
M = 3.996 mol/L⁻¹
It is the first option bc if it absorbed heat it it will pressurize and could explode.
