Chemistry Paper 61

[Nawaf Dandachi]

Exothermic is also write for chemical reaction. I'm definetly sure about it.

YOU DON'T SAY? All displacement are Exo. Plus be simple. It's Double Displacement. There is no direct clue for being exo they didn't mention anything about temp.

 

[Micro961]

Reaction should be Double Displacement.

Effect of Silver Nitrate : Yellow Precipitate

The 2nd graph is line of best fit. you should get 13.5-14-14.5 as an answer of that graph interpret ion question.

Purity of crystals by melting point or chromatography.

Method of separation : Filtration

Last question : Measure masses of steel before and after leaving in water with equal amounts of inhibitor. Mass should increase. the lightest was put in water with the most effective inhibitor. be fair in volume and conc of water , and volume of the inhibitor , and mass of the steel.

Cupper instead of glass will increase temperature rise as copper is a good conductor of heat . Glass is bad conductor of heat.

Method of separation? I don't remember this question at all..

 

[EpicLol]

Its not double displacement I think....its just displacement....

 

[Micro961]

YOU DON'T SAY? All displacement are Exo. Plus be simple. It's Double Displacement. There is no direct clue for being exo they didn't mention anything about temp.

I already solved a past paper about it, they said exothermic so shut up please.

 

[Srhmnir]

i don

Temperature rise will increase because copper is a good conductor of heat.

t think so i wrote the diffrence will decrease as its a condutor of heat so heat will be lost not gained !! i guess thats right

 

[thats_me]

Boiling, To reach crystallization point. Helps dry the mixture and remove water of crystallization. Obtain crystals. Followed by filtration.

hw will it form crystals wen the water of crystalization is lost?

 

[thats_me]

i don
t think so i wrote the diffrence will decrease as its a condutor of heat so heat will be lost not gained !! i guess thats right

even i wrote the same :\

 

[Alan Khaledi]

ok for the checking of purity..I wrote melting point??

well mp n bp r correct bt not practical so I wrote density, but i thnk bp and mp r also correct

 

[thats_me]

Method of separation? I don't remember this question at all..

i guess its the one where they asked to show the apparatus

 

[Nawaf Dandachi]

didn't the question ask us two draw two straight lines that intersect? how come ur saying it's wrong?

Well you can;t just draw 2 lines and intersect them. the first line is best fit, the second is a straight line slope 0. they intersect. the points should be plotted correctly and each 2 boxes 1 mm. the lines should be clear as well and showing the points.

 

[Nawaf Dandachi]

i don
t think so i wrote the diffrence will decrease as its a condutor of heat so heat will be lost not gained !! i guess thats right

Haha That what I thought but no. I changed it and got it correct EL7amdolelah. Just remember when you use cotton to hold hot things. It's a bad conducted so decreases the temp of that thing. thats the same case as the copper and the galss

 

[Nawaf Dandachi]

well mp n bp r correct bt not practical so I wrote density, but i thnk bp and mp r also correct

Melting point. not boiling people.

Chromatography MAY be right.

 

[Nawaf Dandachi]

I already solved a past paper about it, they said exothermic so shut up please.

B**** , in the past paper they state : EXO ENDO only when tempreture is staten in the experiment " Displacment is stated as well.

 

[Hasan Saimeh]

in the second graph we had to draw the graph excluding one point ryte?

No

 

[Nawaf Dandachi]

Its not double displacement I think....its just displacement....

Double displacement. I'm pretty sure of it.

 

[Hasan Saimeh]

which reaction was it?....i wrote displacement

same

 

[Nawaf Dandachi]

Method of separation? I don't remember this question at all..

Number 3. Chockablock separate them from the liquid solution. Draw a labeled filtration process.

 

[Nawaf Dandachi]

It wasn't bad.. I messed up the last question and I lost about 4 marks in the first two pages but the rest was fine.... what do u think of the paper compared to other years in terms of difficulty?? and if I lose about 9 or 10 marks am I still able to get the A*?

The highest curve was 54/60. You'll be fine. Plus it's only 20%

 

[Saadiya Ahmed]

no

u sure?

 

[Nawaf Dandachi]

u sure?

Well the line is of best fit.