Author Topic: CHEM AND BIO HELP AND TIPS HERE  (Read 353858 times)

Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2070 on: May 24, 2010, 08:14:09 pm »
umm y Na and K particularly , y not Ca or Mg

read the q, it says "Single charged" i.e +1

Ca 2+ and Mg2+, no single charged
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Offline The Golden Girl =D

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2071 on: May 24, 2010, 08:15:19 pm »
read the q, it says "Single charged" i.e +1

Ca 2+ and Mg2+, no single charged

i posted this and then i removed it cuz i knew i wasn daydreamin or smthn

thx ...............man i owe u  :o lol  ::)
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Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2072 on: May 24, 2010, 08:17:39 pm »
i posted this and then i removed it cuz i knew i wasn daydreamin or smthn

thx ...............man i owe u  :o lol  ::)

exactly i clicked the link it took me to the top of the page .. i thought somethings wrong with my browser .. :P

Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2073 on: May 24, 2010, 08:18:00 pm »
i posted this and then i removed it cuz i knew i wasn daydreamin or smthn

thx ...............man i owe u  :o lol  ::)

LOL, nah its k, or probably, as stewie griffin might say "Oh most certainly woman, Time will tell. VICTORY IS MINE!"

:P
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Offline The Golden Girl =D

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2074 on: May 24, 2010, 08:18:09 pm »
exactly i clicked the link it took me to the top of the page .. i thought somethings wrong with my browser .. :P

hehe
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Offline CatAly$t

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2075 on: May 24, 2010, 08:19:31 pm »
can somebody help me with this question???i dont understand anything about it... ??? ???
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Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2076 on: May 24, 2010, 08:19:46 pm »
LOL, nah its k, or probably, as stewie griffin might say "Oh most certainly woman, Time will tell. VICTORY IS MINE!"

:P

haha .. LOL :D

Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2077 on: May 24, 2010, 08:22:10 pm »
can somebody help me with this question???i dont understand anything about it... ??? ???

ok liquid Y is water .. tht u got ?? when water is added to anhydrous CuSO4 the colour changes from white to blue and ALWAYS its an exothermic reaction .. so C .. i guess

Offline Ghost Of Highbury

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2078 on: May 24, 2010, 08:22:55 pm »
can somebody help me with this question???i dont understand anything about it... ??? ???

Hydrated copper sulfate --> Anhydrous copper sulfate + water

Anhydrous copper sulfate is white..when water is added , it turns blue.

Adding water to anhydrous copper(II) sulfate is exothermic. thus heat given out.

Answer :C
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Offline Helium

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2079 on: May 24, 2010, 08:24:19 pm »
ok liquid Y is water .. tht u got ?? when water is added to anhydrous CuSO4 the colour changes from white to blue and ALWAYS its an exothermic reaction .. so C .. i guess

SO they were just askin what happens in the reverse reaction
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Offline CatAly$t

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2080 on: May 24, 2010, 08:25:49 pm »
Hydrated copper sulfate --> Anhydrous copper sulfate + water

Anhydrous copper sulfate is white..when water is added , it turns blue.

Adding water to anhydrous copper(II) sulfate is exothermic. thus heat given out.

Answer :C

thanks V1N and adi
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Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2081 on: May 24, 2010, 08:26:43 pm »
SO they were just askin what happens in the reverse reaction


yup .. the question says tht .. when Y is added to X

Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2082 on: May 24, 2010, 08:28:32 pm »

Aadi .. always one step ahead :) .. hey can u tell me how can i been more confidant about my answers ?? like this one for instance ..

when i am confidant the answers go wrong .. :\

Offline the_grim_reaper

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2083 on: May 24, 2010, 08:35:25 pm »
Guys is there a specific volume for which a pipette can be used? I mean a range of volumes???

Offline Vin

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Re: CHEM AND BIO HELP AND TIPS HERE
« Reply #2084 on: May 24, 2010, 08:37:33 pm »
Guys is there a specific volume for which a pipette can be used? I mean a range of volumes???

typical ones in a lab 10, 25, and 50 ml. (at least in my school lab) y do you ask ??