Chemistry: would someone verify my work, please?

  • Thread starter Thread starter bjoyful
  • Start date Start date
  • Tags Tags
    Chemistry Work
Click For Summary
SUMMARY

The discussion revolves around calculating the percent of nitrogen by mass in coal represented by the formula C135H96O9NS and determining the mass of nitrogen produced as NO when three tons of coal are burned. The calculations show that nitrogen constitutes 0.734% of the coal's mass. When three tons (6000 lbs) of coal are burned, 42.8 kg of NO is produced, which includes nitrogen. The participants confirm the calculations and clarify that the focus should be on the mass of NO rather than just nitrogen.

PREREQUISITES
  • Understanding of chemical formulas and molecular weights
  • Basic knowledge of stoichiometry
  • Familiarity with mass percent calculations
  • Ability to convert between pounds and grams
NEXT STEPS
  • Learn about stoichiometric calculations in combustion reactions
  • Study mass percent calculations in chemistry
  • Explore the properties and calculations involving nitrogen oxides (NO and NO2)
  • Investigate the environmental impact of nitrogen emissions from coal combustion
USEFUL FOR

Chemistry students, environmental scientists, and anyone involved in combustion analysis or studying the chemical composition of fossil fuels.

bjoyful
Messages
61
Reaction score
0

Homework Statement



Assume that coal can be represented by the formula C135H96O9NS. A. What is the percent of nitrogen by mass in this coal? B. If three tons of coal were burned completely, what mass of nitrogen in NO would be produced? (Assume that all of the nitrogen in the coal is converted to NO in the burning process.) Be sure to show all your calculation work in each case.

The Attempt at a Solution



A.135x12.01=1621.35 (carbon) + 96x1.008=96.76 (hydrogen) + 9x16.00=144 (oxygen) + 1x14.01=14.01 (nitrogen) + 1x32.07=32.07 (sulfur) = 1908.19. 14.01x100/1908.19= 0.734%.

B.First, to find the moles of coal in 6000lbs of coal, I converted the pounds to grams and divided it by the mole weight (6000 x 453.6 / 1908.19 = 1426.27). Since one mole of coal provides one mole of NO, there are 1426 moles of coal and 1426 moles of Nitrogen. NO has a molar mass of 30g/mol, so 30g/mol x 1426 moles = 42.8kg of NO. Therefore, the mass of nitrogen in NO that would be produced when three tons of coal is burned completely is 42kg. (Am I including both nitrogen and oxygen in this figure? I'm only suppose to be looking for nitrogen??)

I want to make sure I have done this right. If not, please point me in the right direction:)
 
Last edited:
Physics news on Phys.org
So you've got 42.8 kg of NO. They want to know how much of this is nitrogen.
 
Is 42.8kg the correct number of NO? Is there a formula to use to find how much of this is N?
 
I've checked your work and it seems that that is the correct answer.

Think about 1 mol of NO. What percent of this (in terms of mass) is nitrogen?
 
The question asks you for the mass of NO, not N. Relax, you have it. You might want to express it in either tons or pounds for completeness.
 

Similar threads

Replies
1
Views
7K
Replies
9
Views
8K
  • · Replies 1 ·
Replies
1
Views
5K
  • · Replies 1 ·
Replies
1
Views
5K
  • · Replies 7 ·
Replies
7
Views
11K
  • · Replies 4 ·
Replies
4
Views
11K
  • · Replies 21 ·
Replies
21
Views
5K
  • · Replies 18 ·
Replies
18
Views
10K
  • · Replies 4 ·
Replies
4
Views
16K
  • · Replies 19 ·
Replies
19
Views
9K