# An ammonia solution is 6.00 M and the density is 0.950 g/mL. What is the mass/mass percent concentration of NH_3 (17.04 g/mol)?

Sep 29, 2016

#### Answer:

Approx. 10-11%

#### Explanation:

We want to find the quotient: "mass of ammonia"/"mass of solution"xx100%.

We know (i) that $\text{moles of ammonia"/"volume of solution}$ $=$ $6.00 \cdot m o l \cdot {L}^{-} 1$.

We know (ii) that $\text{mass of solution"/"volume of solution}$ $=$ $0.950 \cdot g \cdot m {L}^{-} 1$.

From (i) we know that a $1 \cdot L$ volume of solution contains:

$1 \cdot L \times 6.00 \cdot m o l \cdot {L}^{-} 1 \times 17.03 \cdot g \cdot m o {l}^{-} 1$ $=$ $102.18 \cdot g \text{ ammonia}$

From (ii) we know that, $1 \cdot L$ of solution has a mass of $0.950 \cdot g \cdot m {L}^{-} 1 \times 1000 \cdot m L$ $=$ $950.0 \cdot g$.

And thus "mass of ammonia"/"mass of solution"xx100% $=$

(102.18*g)/(950*g)xx100%~=11% Whewww, arithmetic!!