Equation: M1V1 = M2V2
Where M = concentration & V = volume
Step 1: Write down what is given and what you are trying to find
Given: M1 = 1.25M, V1 = 46mL, and V2 = 250mL
Find: M2
Step 2: Plug in the values into the equation
M1V1 = M2V2
(1.25M)(46mL) = (M2)(250mL)
Step 3: Isolate the variable (Divide both sides by 250mL so M2 is by itself)
(1.25M)(46mL) / (250mL) = M2
Answer: M2 = 0.23M