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General Category => General Discussion => Topic started by: ohcheap1 on September 03, 2009, 05:04:47 PM

Title: HELP!!!! Calling all science nerds!!
Post by: ohcheap1 on September 03, 2009, 05:04:47 PM: 1. Give as example of a chemical change produced by:
a) Light-
b) Electricity-
c) Heat-

2. How would you show that heating a platinum wire in air is a phsical change? Explain.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: hmed2390 on September 03, 2009, 05:09:29 PM: Doing your daughter's homework again for her cheapy? I know that sudden spark of interest in chemistry isn't solely lust driven now. :D ;D
Title: Re: HELP!!!! Calling all science nerds!!
Post by: ohcheap1 on September 03, 2009, 05:12:40 PM: Amen!!! You got my number Hmed now just give her an answer or a place to start to find an answer. Pleeeeeeeease......
Title: Re: HELP!!!! Calling all science nerds!!
Post by: JackFrost on September 03, 2009, 05:16:15 PM: 1. Give as example of a chemical change produced by:
a) Light - Photosynthesis
b) Electricity - A battery
c) Heat - Bread

2. How would you show that heating a platinum wire in air is a phsical change? Explain.

I'm really not sure on this one
Title: Re: HELP!!!! Calling all science nerds!!
Post by: ohcheap1 on September 03, 2009, 05:24:25 PM: Quote
1. Give as example of a chemical change produced by:
a) Light - Photosynthesis
b) Electricity - A battery
c) Heat - Bread
If that ^ is correct is the following v also? This is one she already completed.
2. Give an example of a chemical chage which produces:
a) Light and heat - Lighting a match
b) Electricity- Battery
c) Mechanical energy- burning gasoline (as fuel)
Title: Re: HELP!!!! Calling all science nerds!!
Post by: xtopave on September 03, 2009, 05:26:33 PM: 1)

a) I thought of photosynthesis too but here's another: changes on billirrubine (I don't know how to spell it in English) structure when you expose an icteric baby to ultraviolet light.

b) Electrolysis (contrary of a battery)

c) Coagulation (denaturalization) of proteins by heat (ex: egg)

2) When you stop the process the qualities of the material (platinum wire in this case) aren't altered. Opposed as when a chemical change takes place.
Does this make sense?
Title: Re: HELP!!!! Calling all science nerds!!
Post by: xtopave on September 03, 2009, 05:31:16 PM: Quote from: ohcheap1 on September 03, 2009, 05:24:25 PM
If that ^ is correct is the following v also? This is one she already completed.
2. Give an example of a chemical chage which produces:
a) Light and heat - Lighting a match
b) Electricity- Battery
c) Mechanical energy- burning gasoline (as fuel)

The third isn't correct. Electric energy taken from a waterfall is an example of mechanical energy transformed in another kind. Also rubbing hands generating heat could be an example.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: ohcheap1 on September 03, 2009, 05:33:17 PM: Quote from: xtopave on September 03, 2009, 05:26:33 PM
2) When you stop the process the qualities of the material (platinum wire in this case) aren't altered. Opposed as when a chemical change takes place.
Does this make sense?

I know its difficult for you to analyse and then translate into english but this one is alittle hard for her to grasp. Geesh.....you really do know everything xtopave!!!
Title: Re: HELP!!!! Calling all science nerds!!
Post by: xtopave on September 03, 2009, 05:40:06 PM: First of all I misinterpreted point 3). If what you mean is the transformation of chemical energy (fuel) into mechanical energy (movement of the car) then it's correct.

Second: A physical change doesn't alter the characteristic of matter as opposed to a chemical change which does exactly that. The platinum wire before and after the heating is absolutely exactly the same.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: jackalope21 on September 03, 2009, 06:03:18 PM: Quote from: ohcheap1 on September 03, 2009, 05:04:47 PM

2. How would you show that heating a platinum wire in air is a phsical change? Explain.

If a shiny platinum wire is heated, it will glow with a red color. But when it is removed from the flame, it regains the properties it had before heating. This color change is then a physical change because the composition and physical properties remain the same.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: ohcheap1 on September 03, 2009, 07:00:53 PM: Group Hug!!!
(http://www.clipartof.com/images/emoticons/xsmall2/2407_group_hug.gif)
I thank you and Anna thanks you.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: xtopave on September 03, 2009, 07:04:26 PM: I hope it helped somehow. I thought of more things later but I remember how it was when doing homework: just do it and move on. :D Can I ask how old is she?
Title: Re: HELP!!!! Calling all science nerds!!
Post by: ohcheap1 on September 03, 2009, 07:23:32 PM: 15 and in advanced placement chemistry. She had completed the whole 100 question homework assignment but those 2 stumped her. Of course she completely understands now that she sees the answers but I think her brain was just on overload.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: xtopave on September 03, 2009, 09:59:54 PM: 100 questions like that when you're 15 can crash your brain. :D
Title: Re: HELP!!!! Calling all science nerds!!
Post by: hmed2390 on September 03, 2009, 10:01:30 PM: Awesome everybody. 8)
Sorry OC1, I fell asleep before I could respond :-[
But you got much better answers than I would have come up with :D :)
Title: Re: HELP!!!! Calling all science nerds!!
Post by: smokester on September 04, 2009, 04:19:06 AM: Quote from: ohcheap1 on September 03, 2009, 05:04:47 PM
1. Give as example of a chemical change produced by:
a) Light-
b) Electricity-
c) Heat-

2. How would you show that heating a platinum wire in air is a phsical change? Explain.

Call Methiah.

Peace out.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: subvinorosa on September 04, 2009, 07:26:31 AM: So glad am out of high school. :)

Hope your daughter does well.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: hmed2390 on September 06, 2009, 04:07:42 AM: Quote from: subvinorosa on September 04, 2009, 07:26:31 AM
Hope your daughter does well.

OC1's doing her home, ....I mean, of coarse she will, she's got lots going for her. ;D

@ cheapy, :-* ;)
Title: Re: HELP!!!! Calling all science nerds!!
Post by: xtopave on September 06, 2009, 02:50:28 PM: She must be doing something right. :) She has a 15 years old that still comes to her for help. I'll be glad if mine still talks to me when she's her age.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: Robin-Graves on September 06, 2009, 07:57:19 PM: My 16 year old talks to me about everything.....
I wish I got as much action as he does.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: hmed2390 on September 11, 2009, 01:01:27 AM: Quote from: Robin-Graves on September 06, 2009, 07:57:19 PM
I wish I got as much action as he does.

:P
Title: Re: HELP!!!! Calling all science nerds!!
Post by: ohcheap1 on September 11, 2009, 08:32:09 PM: Quote from: hmed2390 on September 06, 2009, 04:07:42 AM
OC1's doing her home, ....I mean, of coarse she will, she's got lots going for her. ;D

@ cheapy, :-* ;)

Quote from: ohcheap1 on September 03, 2009, 07:23:32 PM
15 and in advanced placement chemistry. She had completed the whole 100 question homework assignment but those 2 stumped her. Of course she completely understands now that she sees the answers but I think her brain was just on overload.

Helping is different from doing. She is smarter than I am in subjects like science so I do what I can to help and this was it. Like I said she was able to completely see what she was missing after it was presented to her.
Title: Re: HELP!!!! Calling all science nerds!!
Post by: JackFrost on September 12, 2009, 01:24:53 AM: So, how'd she do?
Title: Re: HELP!!!! Calling all science nerds!!
Post by: hmed2390 on September 12, 2009, 03:17:20 AM: Quote from: ohcheap1 on September 11, 2009, 08:32:09 PM
Helping is different from doing. She is smarter than I am in subjects like science so I do what I can to help and this was it. Like I said she was able to completely see what she was missing after it was presented to her.

I know, I was teasing you. ;)

She sounds like a very bright young girl, I'm sure you're proud. :)