 # EvoN1020v

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532

## Everything posted by EvoN1020v

1. No, it's not too hard to memorize all of them when you are used to them everyday in your chemistry classes.
2. ## Can someone help me how to do this

Use the formula $\triangle H_{vap} = n \cdot H_{vap}$ You have the total enthalpy change and the moles of the chemicals. You should be able to solve it.
3. ## Having problems with math problem

Omit.
4. ## Having problems with math problem

Integral of $x^2 + y^2$ is $\frac{1}{3}x^3 + \frac{1}{3}y^2 + C$. Thought this might help.
5. Sometimes Lithium (Li) is used too.
6. Seemingly ku (the OP) hasn't posted to answer any of our questions and comments.
7. The second derivative is: $\frac{e^{\frac{1}{x}}(-1+2x)}{x^4}$. Now, Math89, I hope you can detect a pattern in the derivatives?
8. Check it yourself DH. I just edited my post. Therefore, the derivative rule that I used was not wrong.
9. What I got at first was: $e^{ \frac{1}{x}} \cdot ln e \cdot \frac{-1}{x^2}$ according to the derivative rule: $a^u = a^u \cdot lna \cdot u'$. The answer produced was: $-\frac{e^{\frac{1}{x}}}{x^2}$, which apparently is the correct answer according to the integrator tool here at http://integrals.wolfram.com/index.jsp. In conclusion, the derivative of $e^{\frac{1}{x}}$ is $-\frac{e^{\frac{1}{x}}}{x^2}$. Sorry for all the confusion, Math89.
10. Aren't you in the same competition as other guy in other thread? He was asking the similar question.
11. My guess is 999 because it's resourceful.
12. My mistake. You don't have to use chain rule, because there's no other function in $\frac{1}{x}$. Rather you have to use logarithm differiaitation. I got the answer of $e^{\frac{1}{x}}(\frac{-lne}{x^2} + \frac{lne}{x})$. It might be wrong. What do you think? I have a question though. What is the derivative of $ln(e)$? Because when they are together, they produce only $1$. So if the derivative of ln(e) is 1, then the answer would be: $e^{\frac{1}{x}}(\frac{-1}{x^2} + \frac{1}{x})$ or rather $e^{\frac{1}{x}}(\frac{-x+x^2}{x^3})$.
13. You need to use the chain rule to find the first derivative of $e^{\frac{1}{x}}$. Can you tell us what you got?
14. That's right. It's just a special silver chain necklace.
15. I don't see why your daugther can't wear jewelry, because she won't get hurt from wearing it. I'm a Christian myself, and I still wear necklaces. In fact, I am wearing this necklace for two straight years without removing it because it is very valuable to me. My mom gave it to me for my sixteenth birthday. Maybe your wife is just a firm believer comparing to me.
16. A human fact stated that more germs are transferred by shaking hands than kissing. Of course, it's true, because you shake hands with strangers rather to kissing your partner.
17. Ah, understood. My apologies.
18. jdurg, did you read my Element 118 thread at all? "[Element 118] is also one of the shortest-lived, decaying in less than a millisecond." (extracted from the Element 118 thread)
19. Those kids in Africa get abnormal big bellies, because their stomach is eating itself. I'm serious, eating itself. Eating its own organs for their source of energies.
20. Victor Sorok, do you mind using Latex next time? No offence, but your posts are full of scribbles which means it's hard to read your assumed ideal proof. Thank you.
21. ## Japanese scientists cage light

23. Lets hope a new year will brings us new experiences and fonding memories!!
24. ## Can a student with no science background excel in science?

By bat sonnar, you mean bat sonar.
25. I thought so. Do you guys want me to put up more cool mnemonics?
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