A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

Just a simple chemistry question (I am posting it here as the Chemistry study group is DEAD)

  • This Question is Closed
  1. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Calculate the concentration of water and table salt, when 250 grams of table salt NaCl is in 3 litres of liquid. Table salt has a molecular mass of 58,5 g/mol. Give the answer in two decimal precision.

  2. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I know the formula for moles and concentration, which is mol=mass/RMM and conc=mol/volume I did the calculations, but I am still not sure if I am correct, I got 1.42 as the final answer. And I don't know what units it should be in, is it Molarity (that would be 1.42M) or mol/l, or mol/dm^3?? so, if anyone can tell me if I am right about the answer being 1.42 and also what units I should use, it would be great.

  3. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Oh, are you looking for molars?

  4. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    mol per liter?

  5. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\frac{250g}{58.5g/mol}=4.27mol\]so the concentration will be\[\frac{4.27mol}{3L}=1.42M\]

  6. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    great, so I was right :) so I always have to use Molars right? M?

  7. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Depends on what they want. Typically it's that. Another kind of concentration is the 'molal' which is moles of solute ----------------- mass of solvent in kg

  8. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ok, btw, do you know what exactly is constant forward carrying force? is it just mass*acceleraltion? or something involving momentum?

  9. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I've never heard Newton's Second Law of Motion called 'constant forward carrying force'...

  10. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[F=\frac{dp}{dt}\]where p is momentum and F is force. This is the 'proper' definition of force. If then, you take momentum, p, as\[p=mv\]then\[F=\frac{dp}{dt}=\frac{d(mv)}{dt}=m \frac{dv}{dt}=m a\]

  11. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    oh, ok, because I have this simple question and I just wanted to be sure..

  12. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    When there's no speeds are small compared to speed of light.

  13. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    np

  14. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Motorcyclist (total mass 320 kg) stops from a velocity of 36 km/h in 25 s without breaking. The same motorcyclist accelerates in the same conditions from full stop to velocity of 126 km/h in 6 s. Calculate the constant forward carrying force of the engine, if the forces restricting the motion remain constant. Give the answer in 1 N precision. so, I used the newton's second law of motion and found the answer to be 1867N. Is that right? my calculations were like this: converted 126km/h to 35m/s F=\frac{dp}{dt} F=\frac{(35*320)}{(6)} F=1866.66 F=1867N am I right? or did I miss something important?

  15. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    gtg, will be back in like 15 min

  16. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Hey, because I'm fried (it's 230am here) and didn't want to leave you hanging, I found this website that has the question you just asked AND solution: http://www.algebra.com/algebra/homework/testmodule/testmodule.faq Go nuts!

  17. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I have to sign out - my eyes are burning -.- Study hard!

  18. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ok, thanks !!! You are a real HERO!

  19. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.