A few drops of NaOH solution was added to an unknown salt forming a white precipitate which is insoluble in excess solution. The cation likely present is

blaq001

2 years ago

let's get this down sodium,lead and aluminum are soluble in excess NaoH


but calcium is insoluble in excess NaoH
due to the Ca(OH)2 that is formed

Makossa

3 years ago

calcium normally forms brick red or orange colour the answer is Zinc

Ayanshola0619

4 months ago

complicated asf

ArSeDoLaNi

4 years ago

I also think it is zn

Chi4sure

2 years ago

Al3+ and Ca2+ both forms a white precipitate when Naoh is added to it but that of Al3+ dissolves when Naoh is added in excess but that of Ca2+ remains so the correct answer is C

DMI

1 year ago

why don't question 31 to 45 have video explanations

ArianeJoanna

7 years ago

It is Zn+

TheLivingLegend01

3 years ago

Out of the given options, Zn2+ and Pb2+ ions form soluble hydroxides when NaOH is added in small quantities. Therefore, they are unlikely to form a white precipitate.

Calcium ion (Ca2+) forms a white precipitate of calcium hydroxide (Ca(OH)2) when NaOH is added in small quantities, but this precipitate is soluble in excess NaOH. Therefore, calcium is also an unlikely cation.

Aluminum ion (Al3+) forms a white precipitate of aluminum hydroxide (Al(OH)3) when NaOH is added in small quantities, and this precipitate is insoluble in excess NaOH. Therefore, aluminum is the cation likely present in the unknown salt.

Therefore, the correct answer is D. Al3+

Kevin_Aro

3 years ago

When a few drops of NaOH solution are added to a solution containing Al3+, Ca2+, or Mg2+ ions, a white precipitate is formed. However, if excess NaOH solution is added, the aluminum hydroxide precipitate dissolves to form a colorless solution while the calcium and magnesium hydroxide precipitates remain unchanged1. Based on this information, the cation likely present in the unknown salt is Al3+.

So the correct answer would be D. Al3+.