Check my Answer - Let me know if its right or wrong

  • Thread starter benworld
  • Start date
In summary, the given mixture is 45.0% NaCl and 55.0% BaCl2 * 2H20. After heating 4.165 g of the mixture until all of the hydrate is decomposed, 3.58644 g of solid residue will be left. This is calculated by finding the moles of each component, determining the weight of water contained in BaCl2 * 2H20, and subtracting it from the initial weight of the mixture.
  • #1
benworld
7
0

Homework Statement



A mixture is 45.0 % of NaCl (inert) and 55.0 % BaCl2 * 2H20 . If 4.165 g of this mixture is heated until all of the hydrate is decomposed, what mass of solid residue will be left ?


Homework Equations



1 mole substance = grams of substance
1 mole of substance = 6.022E23 of substance ( avogardo number)
Nacl = 58.443
Bacl2*2H20 = 244.236

The Attempt at a Solution



1.

4.165 g Nacl(s)Bacl2*2H20 | 1 mole of Nacl + Bacl2*2H20
--------------------------------------------------------- = 0.0137 mol
| 302.679 g Nacl + Bacl2 * 2H20

2.

0.0137 mol Nacl+Bacl2*2H20 | 1 Mole of Nacl + Bacl2
------------------------------------------------ = 0.00685
| 2 Mole of 2H20

3.

0.00658 mol Nacl + Bacl2 | 266.679 Nacl + Bacl2 (mass)
----------------------------------------------------- = 1.75 | 1 mole of Nacl + Bacl2


Final Answer = 1.75 g of Nacl Bacl2

does this sound right ?


Thanks
Ben
 
Physics news on Phys.org
  • #2
Did you use any of those % you are given, they are important.
 
  • #3
No, How do I use them in formula ? is my setup wrong ?
 
  • #4
% are usually by mass if not specified otherwise.

So of the 4.165g 45% is NaCl and 55%is BaCl2. Considering that you can find out the mass of salt and the mass of hidrated BaCl2. From there you get the moles then the weight of the water contained and finally by substracting the mass of water from the initial weight you get your answer.
 
  • #5
how about this

2.20975 g | 1 mol
------------------ = 0.00904 mol BaCl2*2H20
| 244.20 g

0.00904 mol | 2 mol H20
----------------------- = 0.01808
1 mol of Bacl2 * 2H20

0.01808 mol | 36 g
---------------- = 0.65088 g
1 mol

4.165 - 0.65088 g = 3.51412 g

?

Answer = 3.58644 g
 
  • #6
benworld said:
how about this

2.20975 g 4.165*0.55=2.29075 | 1 mol
------------------ = 0.00904 mol BaCl2*2H20
| 244.20 g

0.00904 mol | 2 mol H20
----------------------- = 0.01808
1 mol of Bacl2 * 2H20

0.01808 mol | 36 g Why 36 h20 has 18!
---------------- = 0.65088 g
1 mol

4.165 - 0.65088 g = 3.51412 g

?

Answer = 3.58644 g
Some corrections above
 

1. Is it okay to ask someone to check my answer and let me know if it's right or wrong?

Yes, it is perfectly fine to ask for someone to check your answer and provide feedback on its accuracy. In fact, seeking feedback is an important part of the scientific process and can help improve the quality of your work.

2. How do I know if my answer is correct?

The best way to determine if your answer is correct is to double check your calculations and make sure you have followed all necessary steps. It can also be helpful to consult with a peer or mentor to get a second opinion.

3. Should I just rely on others to check my answer or should I also check it myself?

While it is helpful to have others check your answer, it is also important to take responsibility for your own work and make sure you have thoroughly checked your answer for any mistakes. This will not only improve the accuracy of your work, but also help you develop critical thinking skills.

4. How do I handle situations where my answer is incorrect?

If your answer is incorrect, it is important to try to identify where you went wrong and learn from your mistakes. You can also ask for feedback from others and work on improving your understanding of the topic.

5. Is it considered cheating to ask someone to check my answer and let me know if it's right or wrong?

No, this is not considered cheating as long as you are not asking someone to give you the answer or do the work for you. Seeking feedback is a valuable part of the scientific process and can help improve the quality of your work.

Similar threads

  • Biology and Chemistry Homework Help
Replies
2
Views
7K
Back
Top