Question

1000.0 ml of water is added to 300.0 ml of 5.00 m h₃po₄. determine the new molarity. m₁ = 5.00 mol/l v₁ = 300.0 ml v₍h₂o₎ = 1000.0 ml v₍f₎ =? ml m₍f₎ =? mol/l multiple - choice m₍f₎ = 1.5m 1.15m 5m 21.7m rewatch

Explanation:

Step1: Calculate final volume

$V_f=V_1 + V_{H_2O}=300.0\ mL+ 1000.0\ mL = 1300.0\ mL$

Step2: Use dilution formula $M_1V_1 = M_fV_f$

$M_f=\frac{M_1V_1}{V_f}$
Substitute $M_1 = 5.00\ mol/L$, $V_1=300.0\ mL$ and $V_f = 1300.0\ mL$ into the formula.
$M_f=\frac{5.00\ mol/L\times300.0\ mL}{1300.0\ mL}\approx1.15\ mol/L$

Answer:

$1.15M$