Dencology

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A catalyst will change:


  • the reaction mechanism ( does this mean that Ea decreases?)
  • the energy of activation
  • the specific rate constant (what is this constant anyways?)
  • two of these
  • all of the above

so I always get this mixed up. I know B is true but what about C and A? these kind of questions always get me.
 

zuma35

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A) Think of an acid or base catalyst taking part in the reaction mechanism of an organic reaction.

C) Rate constant is a measure of the speed of a reaction. A catalyst makes a reaction go faster so it increases the rate constant.
 
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Dencology

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Mar 7, 2008
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A) Think of an acid or base catalyst taking part in the reaction mechanism of an organic reaction.

C) Rate constant is a measure of the speed of a reaction. A catalyst makes a reaction go faster so it increases the rate constant.
hey Zuma:

thanks.

i have one more question:

An egge cell will contain:

a. 23 chromosomes, 46 chromatids
b. 23 chromosoems, 23 chromatids

ans is B but why?

a chromosomes has two chromatides so it would make A the true answer but it is not. can you explain why?

thanks.
 

zuma35

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Basically, in meiosis, one chromosome splits into two chromatids which each become a chromosome in the daughter cell. Look at meiosis in a text book if it's still unclear.
 
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Dencology

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Basically, in meiosis, one chromosome splits into two chromatids which each become a chromosome in the daughter cell. Look at meiosis in a text book if it's still unclear.

i still don't get it.
 

chessxwizard

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The egg carries 1/2 of the human genome and is haploid. Therefore, it would have 23 chromosomes. It does not undergo mitosis until it is fertilized, therefore does not need to duplicate its chromatids. Therefore, it only has 23 chromatids, one corresponding to each chromosome it possesses.
 
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Dencology

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Mar 7, 2008
396
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The egg carries 1/2 of the human genome and is haploid. Therefore, it would have 23 chromosomes. It does not undergo mitosis until it is fertilized, therefore does not need to duplicate its chromatids. Therefore, it only has 23 chromatids, one corresponding to each chromosome it possesses.

thanks buddy.