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Thank you!
2. ### How to prepare 500 mL of 0.025 M of Glucose solution?

answer to your first question 1) 500/1000 X 0.025 moles of solution = 0.0125 moles? answer to your second question 2) 0.0125 X 1000 = 12.5 mL?
3. ### How to prepare 500 mL of 0.025 M of Glucose solution?

0.0125 X 1000 = 12.5 mL?
4. ### How to prepare 500 mL of 0.025 M of Glucose solution?

Homework Statement : I am using a virtual chemistry laboratory and the directions for the first lab experiment says to prepare 500 mL of 0.025 M of glucose solution by diluting the 1 M glucose solution. (I am re-posting this question due to the fact that the previous one was deleted because it...
5. ### B Why do black holes have infinite density, mass, and gravity?

That makes no sense. If Kaku meant that, he should have said so instead of making it confusing and misleading for the laymen. Saying a black hole has infinite density is not the same as saying finite mass in zero volume. << Mentor Note -- Insult removed from post >>
6. ### B Why do black holes have infinite density, mass, and gravity?

In a science documentary, Michio Kaku mentioned that the singularity of black holes have infinite density and infinite gravity. How can laymen expect to learn anything or trust scientists if what some scientists say is not what other scientists believe and scientists never agree with each other...
7. ### B Why do black holes have infinite density, mass, and gravity?

If stars have finite mass, gravity, and density, why does a black hole have infinite density, mass, and gravity and why doesn't it attract everything around it with such infinite gravity? Also, with infinite density, why are black holes all different sizes?

okay, thanks
9. ### B The position of a particle/electron question

Can you explain this in simpler words? What is an "operator" and what do you mean by "different subsystems" and "dynamics are uncoupled which is why they commute"? I don't know what an operator is, and I also don't know what a subsystem or uncoupled dynamics is. Why do they commute from...
10. ### B The position of a particle/electron question

What is the "momentum operator" and what do you mean that it "commutes with the position operator of relative motion"?? Also, what is the atom's "center of mass"? And what do you mean that the "electron density distribution would be spread evenly across an infinite volume of space"?
11. ### B The position of a particle/electron question

When scientists say the position of a particle or electron cannot be known at the same time as its speed, do they mean the particle's position in reference to jumping from energy levels in a single atom, the position in reference to traveling around the nucleus of an atom, or do they mean...
12. ### A Source for First Physics and Chemistry Research Papers?

I want to know if there is a good online source to find and read first-time research papers written by undergraduates(bachelor's research papers) to get a feel for how to write a first research paper in Physics or Chemistry. Can you give me some good places online?
13. ### Find the distance between Helsinki and Seattle.....

I am understanding the problem better than I at first did
14. ### Find the distance between Helsinki and Seattle.....

The astronomy book gives me this problem as the first problem in the book.
15. ### Find the distance between Helsinki and Seattle.....

I am reading the page on the link you gave me, I will get back to you when I have figured it out.
16. ### Find the distance between Helsinki and Seattle.....

That still doesn't really help me. The astronomy book that I have does a poor job at explaining the steps. I'm trying to study on my own
17. ### Find the distance between Helsinki and Seattle.....

Homework Statement This is an astronomy problem. I know how to find cos(AOB) but I am not sure what to do after this. Find the distance between Helsinki and Seattle along the shortest route. Where is the northernmost point of the route, and what is its distance from the North Pole? The...
18. ### B A Speed of Light Theoretical Question

Let's say a mother ship is traveling at the speed of light. If you shoot a pod out of the mothership at the speed of light(and that pod is already traveling at the speed of light), then wouldn't that pod be traveling at twice the speed of light? And if you have a second pod speeding away from...

20. ### Applying Newton's Universal Law of Gravitation

Homework Statement This problem only requires to find h, but I want to make sure that I also found Me and g correctly. Starting with Newton's Law of Gravitation, determine the height h one person has to go from the surface of the earth in order for that person's weight to be reduced to...
21. ### Simplifying a fraction

The only factoring I can see to do is: (5(20a2 + 5))/(3(3x2 - 27y2)) = (4a2 +1)/(x2 - 9y2) and then put these together: (3(2x + 4y))(4a2 + 1)/(5(2a +1))(x2-9y2)
22. ### Simplifying a fraction

I think i made a mistake: (3(x+4y))/(5(2a+1)) times (5(20a2 - 5))/(3(3x2 - 27y2)) (3(x+4y)) should have been: (3(2x+4y))
23. ### Simplifying a fraction

(6x+12y)/(10a+5) times (100a2 - 25)/(9x2 - 81y2) = (3(x+4y))/(5(2a+1)) times (5(20a2 - 5))/(3(3x2 - 27y2))
24. ### Simplifying a fraction

Let me try this again and see what I come up with
25. ### Simplifying a fraction

Homework Statement Simplify (6x+12y)/(10a +5) times (100a2 - 25)/(9x2 - 81y2) Homework Equations (6x+12y)/(10a +5) times (100a2 - 25)/(9x2 - 81y2) The Attempt at a Solution (6x+12y)/(10a +5) times (100a2 - 25)/(9x2 - 81y2) = 3(2x+4y)/(10a+5) times (4a - 1)/(3x-27y) =...
26. ### Did I get this right? Simplifying a fraction

Homework Statement Simplify: (a2 + 2ab + b2)/(a2 - b2) times (a2 - 2ab + b2)/(a2 - b2) Homework Equations (a2 + 2ab + b2)/(a2 - b2) times (a2 - 2ab + b2)/(a2 - b2) The Attempt at a Solution Did I simplify this correctly?? (a+b)(a+b)/((a-b)(a+b)) times (a-b)(a-b)/((a-b)(a+b)) = ((a+b)/(a+b))...
27. ### Multiplying a fraction

Okay, I think I have it now: (x2 + 2x + 1)/(18cw3) times (12c3w)/(x2-1) = (x+1)2(12c3w)/(18cw2)(x+1)(x-1) Cancel the (x+1) = (12c3w)(x+1)/(18cw2)(x-1) Cancel the c and w = (12c2)(x+1)/(18w)(x-1) divided by 3 (numerator and denominator) = (4c2)(x+1)/(6w)(x-1) divided by 2 (numerator and...
28. ### Multiplying a fraction

How did you get 2c2(x+1) when it was 4c2/(x+1)?? Isn't the numerator supposed to be 2c2(2x+2)?? And the denominator is supposed to be: 2w2(3x-3)??
29. ### Multiplying a fraction

Like this?: (x+1)/(6w2) times (4c2)/(x-1) = 4c2x + 4c2/6w2x-6w2 = 2c(2cx+2c)/2w(3wx-3w)<------(Answer)?
30. ### Multiplying a fraction

So the answer is: (x+1)/(6w2) times (4c2)/(x-1)