Question

Gravimetric analysis questions.

Answer 1

A student performed a gravimetric analysis of an unknown solid sample by precipitating the aluminum using 8-HQ, forming the Al(HQ)3 complex as you will do in this lab. If the precipitate, after subtracting the crucible and microfilter, weighed 1.2176 g, what is the mass (in g) of aluminum in the precipitate?

Answer 2

I don't need specifics. I just need to know the approach to this problem.

Answer 3

\[Al^{3+}+3C _{9}H_{6}(OH)N: \rightarrow Al[C_{9}H_{6}(O^{-})N:]_3 \downarrow 3H^{+}\]

Answer 4

abbot can you help me after you help her

Answer 5

I posted it in chemistry

Answer 6

@JoannaBlackwelder when you get the chance...

Answer 7

is it talking about this
\[Al[C_{9}H_{6}(O^{-})N:]_{3}\]
as the precipitate?

Answer 8

that has the mass of 1.2176g how do I find Al?

Answer 9

\[\frac{1.2176g Al[C_{9}H_{6}(O^{-})N:]_{3}}{1}\]

Answer 10

so do i multiply it by moles? i dont get it

Answer 11

\[\frac{1.2176g of Al[C_{9}H_{6}(O^{-})N:]_{3}}{1}*\frac{1mole of Al[C_{9}H_{6}(O^{-})N:]_{3}}{459.3852g of Al[C_{9}H_{6}(O^{-})N:]_{3}}*\frac{1mole Al}{3moles of Al[C_{9}H_{6}(O^{-})N:]_{3}}\]
=\[8.83*10^{-4}moles\]
\[8.83*10^{-4}moles*\frac{26.982gof Al}{1mole}=.0238gof Al\]
@JoannaBlackwelder does this look right?