Chemistry: Post your doubts here!

[A*****]

6 A substance commonly found in the house or garden has the following properties.
• It is combustible.
• It is an electrical insulator.
• It melts over a range of temperature.
What could the substance be?
A brass
B paper
C poly(ethene)
D silicon(IV) oxide
Ans is C

Which year is it?

 

[Hamnah Zahoor]

Which year is it?

oct/nov/2008

 

[A*****]

Can someone plz help me with this one?

 

[Metanoia]

Can someone plz help me with this one?View attachment 63717

Note that except for B, the dipoles for the other 3 options can be viewed as cancelling each other out

 

[A*****]

View attachment 63718

Note that except for B, the dipoles for the other 3 options can be viewed as cancelling each other out

Ohhh thanx alot
May God bless u for that!

 

[hancy pandey]

Any guess paper or prediction for tomorrow practical chemistry P33?

 

[A*****]

Any guess paper or prediction for tomorrow practical chemistry P33?

34*

 

[shevanka]

34*

please email me if you find something - [email protected]

 

[aloo Kha]

paper 34: will there really be organic in no 3?

 

[abbas haider]

Can Anyone Tell what's the accuracy of Burette ,pippete ,meauring cylinder and Thermometer? (how many d.p would i write if i measure from each one of these?)

 

[ghazanfar1234565]

please can any one tell about the ions of p34

 

[Kanekii]

Need help with this.
For the first one i know its a reaction pathway of SN1 reaction but why can it not be A or D since they don't have graphs like that i guess

 

[shevanka]

please can any one tell about the ions of p34

please can any one tell about the ions of p34

i think sulphate,copper and iron 2

 

[ba-lock-ey]

Can Anyone Tell what's the accuracy of Burette ,pippete ,meauring cylinder and Thermometer? (how many d.p would i write if i measure from each one of these?)

Thermometer to whole number like 50.0 or to .5 like 64.5
MAKE SURE YOU PUT TO ONE DP, and the only decimals are .0 and .5

Burette 0.05 for each reading.

 

[Mts.99]

Uncertainty in pipette is 0.06?

 

[ba-lock-ey]

Uncertainty in pipette is 0.06?

What type of pipette? 25?

 

[ba-lock-ey]

34*

Practice. I don't think it's right to ask this since the admin of Xtremepapers check the forums and ban people for discussing such questions. Good tip: memorize cation and anion rxns or at least learn to identify what the question is asking so you don't have to waste time going through the last sheet.

 

[Mts.99]

What type of pipette? 25?

yes

 

[angryrider_56]

"Also, study the reaction of kmno4 with glucose from the net. If any reaction equation is available please study equation as well.
Expected practical is organic based. Please study fehlings tollens and iodoform test with equations."
-Got this from a friend...Good luck bois

 

[A*****]

View attachment 63722 View attachment 63723 Need help with this.
For the first one i know its a reaction pathway of SN1 reaction but why can it not be A or D since they don't have graphs like that i guess

In 28 A, an intermediate is formed with O- and so the reaction is a 2 step process
Similarly with D, first 1 Br attaches and a carbocation is formed and so it is also a 2 step pathway