Biology; Chemistry; Physics: Post your doubts here!

[kirann]

e) if 25.9 --> 0.0025 moles
1000 (1dm^3)---> x
25.9x= 2.5
x= 0.0965 moles
Then the formula no. of moles= mass in g/mr
0.0965= 8.50/x
x=88 g
Now seee this CnH2n+1COOH
Total mass= 88g.
COOH= 45g
CnH2n+1= 88-45
= 43g
C3H2(3)+1= 43g.
Therefore the formula is= C3H7COOH.
Need help with the next part?

from where have you got 25.9 ?

 

[asadalam]

Yeah, you may clap for yourself.

I'll clap when i get straight A*s.Its just tension mixed with anxiety and a dash of insomnia right now

 

[funky brat]

from where have you got 25.9 ?

You only need to plot rise in temp. readings.

 

[funky brat]

from where have you got 25.9 ?

It is the average volume.

 

[funky brat]

I'll clap when i get straight A*s.Its just tension mixed with anxiety and a dash of insomnia right now

Insha'Allah. :')

 

[Laibaaa]

10 (a) Describe an experiment to show the difference between an electrical insulator and an
electrical conductor. Name one example of each. [4]

 

[funky brat]

10 (a) Describe an experiment to show the difference between an electrical insulator and an
electrical conductor. Name one example of each. [4]

Umm I just don't know any but you can make it up. Make a circuit, attach some piece of metal to it, current flows. Place a block of wood, current does not flow.

 

[kirann]

It is the average volume.

thanks a tonne buddy

 

[Laibaaa]

(iii) The 1500 Ω resistor on the electronic circuit board has a correct power rating of 0.25 W.
State a disadvantage of using a different 1500 Ω resistor with a power rating that is
1. much less than 0.25 W,
...........................................................................................................................................
...................................................................................................................................... [1]
2. much greater than 0.25 W.
...........................................................................................................................................
...................................................................................................................................... [1]

Sorry, Im just having trouble with some questions. :/ Xtremepapers is my only hope.

 

[kirann]

 

[asadalam]

(iii) The 1500 Ω resistor on the electronic circuit board has a correct power rating of 0.25 W.
State a disadvantage of using a different 1500 Ω resistor with a power rating that is
1. much less than 0.25 W,
...........................................................................................................................................
...................................................................................................................................... [1]
2. much greater than 0.25 W.
...........................................................................................................................................
...................................................................................................................................... [1]

Sorry, Im just having trouble with some questions. :/ Xtremepapers is my only hope.

Post the complete question

 

[Laibaaa]

http://www.taleem-e-pakistan.com/ca...l_physics_past_papers_2011/5054_s11_qp_21.pdf

Pg 12, Q10

 

[kirann]

(iii) The 1500 Ω resistor on the electronic circuit board has a correct power rating of 0.25 W.
State a disadvantage of using a different 1500 Ω resistor with a power rating that is
1. much less than 0.25 W,
...........................................................................................................................................
...................................................................................................................................... [1]
2. much greater than 0.25 W.
...........................................................................................................................................
...................................................................................................................................... [1]

Sorry, Im just having trouble with some questions. :/ Xtremepapers is my only hope.

i came across with this question in my mock...
and i wrote
1. much less resistance would produce after going through the resistor.
2. the components and wire may get damage or melt...
but i dont know the logic behind it.... fortunately i wrote whatever was in my mind at that time
and it was correct.

 

[Laibaaa]

Yeah its correct but the logic behind it?:/ really don't get it

 

[kirann]

can anybody plz explain

 

[kirann]

Yeah its correct but the logic behind it?:/ really don't get it

ill tel this to you by tomorrow I.A

 

[kirann]

HOW CAN I DEDUCE THIS??

 

[Laibaaa]

Suree. I'A and thank you very much

 

[Shahzad Haider]

Can anyone help me to provide guess paper or practise paper by any famous teacher of ATP biology?

 

[kirann]

Suree. I'A and thank you very much

ANYTIME...