Analytical Chemistry Question 185
Question: Sodium carbonate cannot be used in place of $ {{(NH_4)}_2}CO_3 $ for the identification of $ C{a^{2+}},B{a^{2+}} $ and $ S{r^{2+}} $ ions (in group V) during mixture analysis because:
Options:
A) $ M{g^{2+}} $ ions will also be precipitated.
B) Concentration of $ CO_3^{2-} $ ions is very low.
C) Sodium ions will react with acid radicals.
D) $ N{a^{+}} $ ions will interfere with the detection of $ C{a^{2+}},B{a^{2+}},S{r^{2+}} $ ions.
Show Answer
Answer:
Correct Answer: A
Solution:
[a] If $ Na_2CO_3 $ is used in place of $ {{(NH_4)}_2}C{O_3} $ . It will precipitate group V radicals as well as magnesium radicals. The reason for this is the high ionization of $ Na_2CO_3 $ in water into $ N{a^{+}} $ and $ CO_3^{2-} $ . Now the higher concentration of $ CO_3^{2-} $ is available which exceeds the solubility product of group V radicals as well as that of magnesium radicals.
BETA
