Hi Students,
Time to do some practice questions on Mole Concepts. I will be posting a series of essential conceptual questions on Mole Concepts and Chemical Calculations for you to try. Please try it out and leave your working/answer in the “Comment” section directly below this post.
Example:
Which has greater mass, 1.0g of gold or 0.5mol of helium?
PS: “Either You Practice & Use It, or You Loose It!”
hmmm…. 1g of Gold, 0.5 mol of He
Helium is diatomic.
Mass of He
= mol X molar mass
= 0.5 X 8
= 4.0 g
hence, He has a greater mass than 1g of Gold?
Kindly correct me if I am wrong.
Thank you.
Reply
Approach is correct but answer is somehow wrong.
1st, Helium is a rare gas (Group 0 element). As such, it is very stable and exist
as its own as a Monatomic Element. It is NOT A DIATOMIC MOLECULE.
Thus, we will have:
Mass of He
= mol X atomic mass
= 0.5 X 4
= 2.0 g
0.5mol of Helium is heavier than 1g of Gold.
Hope this is clear to you.
Reply