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Biology; Chemistry; Physics: Post your doubts here!

paradoX error

paradoX error

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SulmanAli said:
What is the difference between fleming left hand rule and fleming right hand rule ? i get confused when to apply each of these ? Please Help
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right hand rule is for electromagnetic induction i mean for ac generators whereas left hand rule is used in dc motors both rules are of fleming :p and one more thing the middle finger in left hand rule represent flow of positive charge and in the case of right hand rule it represents flow of electrons
 
ashiqbal

ashiqbal

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colour for copper oxide is black, lead oxide is yellow, question comes on these two colours. most of other oxides are white. chlorine = yellowish-green, bromine = redddish-brown and iodine => solid = black, vapour = purple and iodine gas I2 is brown. no more colours are important, and some are common sense eg metals are shiny silver, etc.
 
bogus

bogus

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nafis shahRiyar said:
No...as in like colours of compounds...for example ammonium sulphate...how could i know the exact colour !!! ..any trick to deduce the colours??:cool:
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all group 1 ,2 , zinc, lead and ammonium compounds are white
cuso4 is blue if hydrated otherwise white
cuco3 is green
cu itself is pink
thats all i can retain :(
 
Mayedah

Mayedah

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Tharindu said:
Does anyone have notes on terelyne....It's not there in the organic section of my book
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Terylene is made by two monomers .it can be made from dicarboxylic acid and an alcohol
For eg two specific monomers i know are ethane -1-2-diol and benzene -1-4-dicaboxylic acid !
These two will combine together and condensation polymerisation will occur .
Ethane 1 2 diol will release OH and benzene will release and H to form a small monomer h2o ( water)
Terylene is also known as polyester bcuz it has ester linkage between each other.ester linkage is the linkage between carbon and oxygen !
 
convent2012

convent2012

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J2011 A germinating seed is soaked in blue dye, which becomes colourless in tissues that are actively respiring.
What will be the appearance of the cotyledons, plumule and radicle?
Cotyledons plumule radicle
A blue blue blue
B blue blue colourless
C colourless blue colourless
D colourless colourless colourless


In maize, one allele of a particular gene allows chlorophyll production while the other allele prevents this, giving plants with cream coloured leaves.
Half the seeds from a cross between two green-leaved plants were sown in trays kept in the dark.
The other half were sown in similar conditions except that they received light.
The table gives the results obtained.
numbers of seedlings
kept in the dark kept in the light
green leaves cream leaves green leaves cream leaves
? 405 320 110
What was the number of green-leaved plants formed from seeds germinating in the dark?
A 0 B 110 C 320 D 405
 
Rimsa

Rimsa

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awaisbuttrocksCIE said:
Bio 21
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draw a hybrid cross. the result is 3:1. the one ratio is recessive.
make a cross of wings and take wing property. and refer to the in the diagram in qp. it shows 6 large winged flies and 2 small winged. the ratio is 3:1 so small winged is recessive.
 
GetSomeLife

GetSomeLife

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Dukeofwin said:
What pressure is the length h used to measure?
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"h" tells you how much greater the gas pressure is than the atmospheric pressure.
If, for example, h=30 mmHg and the atmospheric pressure is 770 mmHg... we can say that the gas pressure is 800 mmHg :)
 
Rimsa

Rimsa

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convent2012 said:
J2011 A germinating seed is soaked in blue dye, which becomes colourless in tissues that are actively respiring.
What will be the appearance of the cotyledons, plumule and radicle?
Cotyledons plumule radicle
A blue blue blue
B blue blue colourless
C colourless blue colourless
D colourless colourless colourless


In maize, one allele of a particular gene allows chlorophyll production while the other allele prevents this, giving plants with cream coloured leaves.
Half the seeds from a cross between two green-leaved plants were sown in trays kept in the dark.
The other half were sown in similar conditions except that they received light.
The table gives the results obtained.
numbers of seedlings
kept in the dark kept in the light
green leaves cream leaves green leaves cream leaves
? 405 320 110
What was the number of green-leaved plants formed from seeds germinating in the dark?
A 0 B 110 C 320 D 405
Click to expand...
the first one is D because all of these tissues respire. thats where the energy comes from.
the second is A i think cuz when if you add total number of seedlings in light, its 430. and in dark, 405 are cream-leaved so the remaining 25 may be lost due to experimental error. and also cuz all other options are larger then 25 =)
 
T

Tharindu

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Mayedah said:
Terylene is made by two monomers .it can be made from dicarboxylic acid and an alcohol
For eg two specific monomers i know are ethane -1-2-diol and benzene -1-4-dicaboxylic acid !
These two will combine together and condensation polymerisation will occur .
Ethane 1 2 diol will release OH and benzene will release and H to form a small monomer h2o ( water)
Terylene is also known as polyester bcuz it has ester linkage between each other.ester linkage is the linkage between carbon and oxygen ![/quote
Thank you
Click to expand...
 
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