Question

1- Quantos gramas devemos pesar para preparar:
a) 400 mL de uma solução 4 mol/L de AgNO3?

Answer 1

$Ol\acute{a}~~\mathbb{NATIELLE} \\ \\ Primeiro~devemos~calcular~a~massa~molar~de~\boxed{AgNO_3}, veja: \\ \\ \boxed{AgNO_3}~\begin{cases}Ag=108 \\ \\ N=1 \\ O=16\end{cases} ~\begin{cases} \\ MM=\underbrace{108+1+16.3 }_{170}\\ \\ MM=\boxed{170g/mol }~--\ \textgreater \ massa~molar\\ ~~~~~~~~~~~~~~~~\end{cases} \\ \\ \star~Temos~que: \\ ~~~~~~~~~~~~~~~~~~ \frac{4\not mol}{1L}. \frac{170g}{1\not mol}=\boxed{680g/L }$

$\star~Tenemos~400ml~vamos~passar~a~litros(L): \\ 400\not ml. \frac{1L}{1000\not ml} =\boxed{0,4L} \\ \\ \star~Ahora~tenemos~que: \\ \\ 1L-----\ \textgreater \ 680g \\ 0,4L----\ \textgreater \ m \\ por~regra~de~tres~temos: \\ \\ \frac{1\not L}{0,4\not L} = \frac{680g}{m}~~--\ \textgreater \ multiplicamos~en~cruz~temos: \\ \\ 1m=680g.(0,4) \\ \\\boxed{ \boxed{m=272g }}~de~AgNO_3$

$\mathbb{vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv} \\~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Espero~ter~ajudado!!$