× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
5
a
5
k
5
c
5
B
5
l
5
C
4
s
4
a
4
t
4
i
4
r
4
Home Q & A Board Science-Related Homework Help Chemistry (Moderator: Laser_3)
New Topic  
datpiff datpiff
wrote...
Posts: 93
Rep: 0 0
11 years ago
How do I calculate the mass of iron in 40 grams of haematite (Fe2O3)?
Please explain and solve.
Read 668 times
1 Reply

Related Topics

Replies
wrote...
#1
11 years ago
Find the number of moles of hematite.  That's how many moles of iron are in the sample.  Then just multiply by the molecular mass of iron to get the mass.

Fe2O3 = 55.85*2+16*3 g/mol (from periodic table) = 159.7 g/mol.

40 g / 159.7 g/mol = 0.25 moles

0.25 moles * 55.85*2 (x2 because there are two atoms of iron in the molecule) = 27.98 g iron.
New Topic      
Quick Reply
Explore
Post your homework questions and get free online help from our incredible volunteers
  1280 People Browsing
Start New Topic Take the Tour CoursesNew Study Tools Topics Trending Browse by Textbook
Live Chat
Related Images
  
 957
  
 187
  
 760
Your Opinion
Who will win the 2024 president election?
Votes: 3
Closes: November 4
Previous poll results: Which 'study break' activity do you find most distracting?