Question

A student requires 2.00 L of 0.100 M NH4NO3 from a 1.75 M NH4NO3 stock solution. What is the correct way to get the solution?
Use M subscript i V subscript 1 equals M subscript f V subscript f..
Measure 114 mL of the 1.75 M solution, and dilute it to 1.00 L.
Measure 114 mL of the 1.75 M solution, and dilute it to 2.00 L.
Measure 8.75 mL of the 1.75 M solution, and dilute it to 2.00 L.
Measure 8.75 mL of the 0.100 M solution, and dilute it to 2.00 L.

Answer 1

Use M_i V_1 = M_f V_f.

V_1 = (M_f V_f) / M_i = (0.100 M × 2.00 L) / 1.75 M = 0.1143 L = 114 mL.

So measure 114 mL of the 1.75 M solution and dilute it to a final volume of 2.00 L.