Chemical Forums
Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Cheerios on September 07, 2014, 08:31:34 AM
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Hello everyone, I'm new to the forums so sorry if this is in the wrong section! I'm currently studying Rates of Reaction.
Q1. Explain why food is kept in freezers in terms of rates of reaction.
I said that freezers reduce temperatures and thus the rates of the reactions that lead to food spoilage are decreased. Can anyone tell me if this is right please?
Q2. Why are reactions between ionic compounds in solution are generally faster than reactions between covalent compounds?
I know I haven't shown any efforts of me trying to solve it but I honestly do not know where to start... Can anyone give me a hint please?
Thanks!
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Question 1)
You are correct; the freezer’s low temperatures are drawing kinetic energy out of the food, decreasing the collisions of the atoms, therefore decreasing the reaction rate.
Question2)
Think about the differences between ionic and covalent compounds in solution:
What are the products of an ionic compound in water? Ions with complete opposite charges, right?
How about covalent compounds in a solvent? At best, there will only be small partial charges.
To what extent will the ionic products be attracted to each other? How about the covalent products? How do you think these attractions effect the rate of the reaction?
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Mate ,
You can think like this..
Answer No. 1.
See ..every reaction has its own pathway....if looked at energy profile of any reaction ..it just look like a mountain...at the left side you are a reactant if you crossed that peak then you can slip down to the product side..
But you must have sufficient energy to reach at the top..
So if you decrease the the temperature the energy of atoms decreased..
Answer No. 2
See in ionic compound ...they just have to just rearrange them self...if one ion feels that i can be more stable than that with this one....then it just get influenced by that ion and attached to it....and in solvents there is much much greater chances to rearrange themselves since their mobility get increased...
But in case of covalent compounds..
They have to break apart themselves....then form an intermediate.....then if they can form a better and a stable intermediates they transformed into them.....then a another collision take place which leads to formation of product..
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For better understanding of answer no. 1...
Here is a picture....
(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fwww.chemguide.co.uk%2Fphysical%2Fbasicrates%2Fsn1profile.gif&hash=b91d5502a1bea3916b59f54c906fecd7504bf44a)
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Thank you two for the helpful replies! I think I got the answers right so thank you all again! You guys helped a ton. :D
Edit: Is there any way of giving +rep to people? :O
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Edit: Is there any way of giving +rep to people?
you can give mole snacks
see under posters name on the post
Also please give better titles to your posts
Please read forum rules -- see link at top of page (dark red shade)
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Sorry, it won't happen again.