given 0.0450 M ca(no3)2 and 0.0350 M fe(no3)2. when i separate them, which compound should be used? Na2co3(aq), Hcl(aq), or naoh(aq)? . and which will precipitate first?
I went with hcl, and for question two, fe^2+
or im thinking naoh, since hydroxide ions can form with fe^2+ to form a solid.
nvm i got it. it is naoh.
To determine which compound should be used to separate the two given compounds, you need to consider their chemical properties and behavior.
Let's start by analyzing the reactions between the given compounds and the three options: Na2CO3 (sodium carbonate), HCl (hydrochloric acid), and NaOH (sodium hydroxide).
1. Na2CO3 (sodium carbonate):
- Sodium carbonate is typically used to identify the presence of calcium ions (Ca2+) in a solution, which form a precipitate (solid) of calcium carbonate (CaCO3). However, it does not react with iron ions (Fe2+).
2. HCl (hydrochloric acid):
- Hydrochloric acid is a strong acid that reacts with both calcium ions (Ca2+) and iron ions (Fe2+). However, the reactions are different for each:
- With calcium ions: HCl + Ca(NO3)2 → CaCl2 + HNO3
This reaction forms calcium chloride (CaCl2), but it remains in solution since it's soluble in water.
- With iron ions: HCl + Fe(NO3)2 → FeCl2 + HNO3
This reaction forms iron(II) chloride (FeCl2), but similarly, it remains in solution.
3. NaOH (sodium hydroxide):
- Sodium hydroxide is often used to identify the presence of iron(II) ions (Fe2+) in a solution, where it forms a precipitate of iron(II) hydroxide (Fe(OH)2). However, it does not react with calcium ions (Ca2+).
Based on these observations, neither Na2CO3 nor NaOH will help in separating both compounds effectively. When you choose HCl as the compound to use, it will indeed react with both calcium and iron ions in the solutions, but no precipitate will form for either compound.
As for the second question, since no precipitate forms when HCl is added, neither compound will precipitate first. Hence, the answer is no precipitate will form.
In summary:
- The recommended compound to use in this scenario would be HCl.
- However, there will not be any precipitate formed when HCl is added to separate the two given compounds.