Anonymous
Anonymous asked in Science & MathematicsChemistry · 4 years ago

# An excess of potassium iodide in solution was shaken with some lead nitrate solution in a test tube. The lead iodide precipitate was?

Separated from the mixture and then washed several times with water. The lead iodide was dried and then placed in a bottle.

1) SUGGEST A REASON WHY EXCESS POTASSIUM IODIDE WAS USED?

2) WHAT WORD USED IN THE PASSAGE SHOWS THAT LEAD IODIDE IS INSOLUBLE?

3) SUGGEST HOW LEAD IODIDE CAN BE SPARATED FROM THE MIXTURE?

4) POTASSIUM NITRATE WAS ALSO FORMED. THIS CAN BE FORMED ANOTHER WAY BY REACTING POTASSIUM HYDROXIDE WITH AN ACID. NAME THE ACID THAT FORMS POTASSIUM NITRATE.

thank you so much if you also these. I have been really stuck on these and I know there is quite a few questions so thank you soooo much.

Relevance
• Anonymous
4 years ago

Pb(NO3)2(aq) + 2KI(aq) ----> PbI2(s) + 2KNO3(aq)

1)One mole of lead nitrate requires two moles KI thus KI may finish first and lead nitrate may be left behind.

(To understand this better you may want to search--limiting and excess reagent).To avoid this KI is taken in excess.

2) The word precipitate shows that lead iodide was insoluble.

3) Lead iodide can be separated by filtration.

4) The acid is nitric acid HNO3, it gives a neutralization reaction with potassium hydroxide to form potassium nitrate.

• zagel
Lv 4
3 years ago

Excess Of Potassium

• Umar
Lv 7
4 years ago

1) To completely precipitate ALL the Pb2+ ions.

2) PRECIPITATE

3) Simple filtration with a good filter paper.

4) Nitric acid (HNO3) ie KOH HNO3 --->KNO3 + H2O