What Is the Percent Yield from Aluminum to Potassium Alum?

[Lili123]

Here is the question: If 75.0 g of potassium alum is obtained from 5.00 g of aluminum, what is the percent yield?

This is what I've done so far, but I'm not sure if it is fully correct:
5.00g Al x (1/26.98156) x (1/1) x 258.207 = 47.84882537g potassium alum

Wouldn't this then be the theoretical yield? But then that wouldn't work because the actual yield of 75.0g is much greater... is there something I did wrong here?

 

[Borek]

5.00g Al x (1/26.98156) x (1/1) x 258.207 = 47.84882537g potassium alum

And you expect us to guess what these numbers mean?

Please start by writing the reaction equation. What is the formula of the alum? Hint: it is not just KAl(SO₄)₂.

 

[insightful]

Another hint: You've been given a three significant figure problem. Piling on significant figures is neither useful nor impressive.