Homework Questions dealing with energy

1. 18g of oxygen is reacted with sufficent nitrogen to make 56g of nitrogen dioxide according the following reaction:

2O[size=7]2[/size](g) + NO[size=7]2[/size](g) :arrow:


If the reaction goes to completion how much nitrogen reacted?


2. If you are boiling some potatoes in a pot of water, will they cook faster if hte water is boiling vigoriously than if the water is only gently boiling. Explain your reasoning.



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hmmm... that 2nd one puzzles me.

when it is boiling vigoriously, that means it is at a higher temperature, but that means that the water is vaporizing quicker and leaving less water to cook the potatos. unless, of course, you have someone right there to add water continuously. P
I don't think that's what they mean though...
i think the latter because that means the water is at a higher temp, but i would trust my opinion because i'm only in chem1 )

Boiling water == 100?C
So I doubt they will cook any quicker - you'll just lose all of the water quicker.

a liquid transfers its heat much better than a gas. If you think about it, a liquid represents much more mass...more mass - more energy stored...more molecule to molecule contact.

More boiling/more gas in the liquid - less heat transfered to the potatoes unless your trying to steam them! Logically this is how I would think it works.

Why don't you set up an experiment of your own? I would be easy to tell if the potatoe cooked better or worse. use a russet though, red potatoes cook too quickly.

You don't loose all the water if you keep the lid on the saucepan!

Honestly, you boys, couldn't boil an egg! lol

[quote="feline1"]You don't loose all the water if you keep the lid on the saucepan!

Honestly, you boys, couldn't boil an egg! :lol:[/quote]
Sorry..... "Boil an egg"
Surely you would need some kinda pressured container to boil an egg, because direct heat would burn the shell and probably the insides along with it.

I think I'll stick to the eggs they serve in Hall :)
Dunno how they make them, but they are always hard yet edible on the inside, and the shell isn't burned one bit.
AND they don't have bunsen burners in the kitchen.

Wonders never cease!

Hey now, don't insult my cooking! Food network taught me how too cook while I've been in college!

oh yeah oops

indeed, conducting experiments is a huge part of chemistry! )
i wonder if the person who posted this ever came back...

ty should attempt the problem before posting :roll:

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