# A lab assistant needs to make up 6.00 liters of .100 M HCI solution. How many liters of 12.0 M HCl solution should she use?

A sufficiency, here $50 \cdot m L .$, i.e. $0.0500 \cdot L$
$\text{Moles of HCl}$ $=$ $6.00 \cdot L \times 0.100 \cdot m o l \cdot {L}^{-} 1 = 0.600 \cdot m o l$.
So we need a volume of conc. acid that contains $0.600 \cdot m o l$.
$\text{Volume}$ $= \text{Amount in moles"/"Concentration}$ $=$ $\frac{0.600 \cdot m o l}{12.0 \cdot m o l \cdot {L}^{-} 1} \times 1000 \cdot m L \cdot {L}^{-} 1$ $=$ $50 \cdot m L .$