A mixture of lead, magnesium, nitrate and chromate ions are present in a solution. What will the precipitate be?
a) MgPb
b) Pb(NO3)2
c) PbCrO4
d) MgCO3
I think its d)- am i right?
To determine the precipitate formed, we need to consider the solubility rules.
Let's break down the compounds:
- Lead (Pb) can form insoluble compounds with carbonate (CO3) ions, so a precipitate could form if carbonate ions are present.
- Magnesium (Mg) can form insoluble compounds with phosphate ions, but there are no phosphate ions present in the mixture.
- Nitrate (NO3) ions are generally soluble and do not form precipitates.
- Chromate (CrO4) ions can form insoluble compounds with lead ions.
Based on the solubility rules, the precipitate formed will be lead chromate (PbCrO4).
Therefore, the correct answer is c) PbCrO4.
To determine the precipitate in a solution, we need to consider the solubility rules for each compound present.
Let's analyze each compound:
a) MgPb - This compound is not commonly encountered. We need to confirm its solubility.
b) Pb(NO3)2 - Lead(II) nitrate is generally soluble in water. However, we need to check whether the other ions in the solution can form an insoluble compound with lead.
c) PbCrO4 - Lead(II) chromate is generally insoluble in water. If lead ions are present in the solution, they can potentially react with chromate ions to form a precipitate.
d) MgCO3 - Magnesium carbonate is generally insoluble in water. If magnesium ions are present in the solution, they can potentially react with carbonate ions to produce a precipitate.
Based on the solubility rules, compounds (c) and (d) have the potential to form precipitates.
To determine the correct answer, we need to identify which of the ions in the solution can form insoluble compounds with lead, magnesium, nitrate, or chromate ions.
1. Nitrate ions (NO3-) are generally soluble and do not form precipitates.
2. Chromate ions (CrO4^2-) have the potential to form a precipitate with lead ions.
3. Magnesium ions (Mg^2+) have the potential to form a precipitate with carbonate ions.
4. Lead ions (Pb^2+) can form precipitates with chromate ions.
Therefore, the precipitate in the solution would be (c) PbCrO4.
So, your initial guess of (d) MgCO3 is not correct. The correct answer is (c) PbCrO4.
No. You need to know the solubility rules. Here is a simplified set. It can't be d because there is no CO3 in the system.
http://www.files.chem.vt.edu/RVGS/ACT/notes/solubility_rules.html