Physics, Chemistry and Biology: Post your doubts here!

[Lost_Life]

yeah, ms says C

OH... THANK YOU SOO MUCH!!

 

[AAnsarii]

Does density increase or decrease as we go down group 1,2,3,4,5,6,7,8
Thx

i think it generally increases
http://www.lenntech.com/periodic-chart-elements/density.htm

 

[Lost_Life]

Does density increase or decrease as we go down group 1,2,3,4,5,6,7,8
Thx

for 1 decreases , but for the rest, i guess they all increase :3

 

[NIM]

Help in this one
http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w04_qp_1.pdf
question 1,11 and 34
Thnx in advance

 

[FATIMAH]

WHY IS A NOT CORRECT ??? SODIUM CHLORIDE IS IONIC COMPOUND AND IONIC COMPOUNDS ARE SOLUBLE IN WATER ???//

 

[EpicLol]

for 1 decreases , but for the rest, i guess they all increase :3

ok so for group 1 metals the density increases as we go down but for the rest it increases as wel go down....

 

[AAnsarii]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w03_qp_1.pdf q 36.
q40- what's d catalyst there?

 

[EpicLol]

Help in this one
http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w04_qp_1.pdf
question 1,11 and 34
Thnx in advance

1-C
11-A

 

[aliiiiiiiiii]

WHY IS A NOT CORRECT ??? SODIUM CHLORIDE IS IONIC COMPOUND AND IONIC COMPOUNDS ARE SOLUBLE IN WATER ???//

View attachment 12823

i think bcause the nacl is in a saprate tube so its not dessolve!!??

 

[Maz]

WHY IS A NOT CORRECT ??? SODIUM CHLORIDE IS IONIC COMPOUND AND IONIC COMPOUNDS ARE SOLUBLE IN WATER ???//

View attachment 12823

Sodium chloride is soluble in water, but in this question, this is not a factor for the incorrectness for this experiment.

 

[Lost_Life]

ok so for group 1 metals the density increases as we go down but for the rest it increases as wel go down....

Yes

 

[EpicLol]

WHY IS A NOT CORRECT ??? SODIUM CHLORIDE IS IONIC COMPOUND AND IONIC COMPOUNDS ARE SOLUBLE IN WATER ???//

View attachment 12823

but there is a glass tube which keeps them from becoming a solution therefore its B

 

[Lost_Life]

Sodium chloride is soluble in water, but in this question, this is not a factor for the incorrectness for this experiment.

what do you mean?

 

[Maz]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w03_qp_1.pdf q 36.
q40- what's d catalyst there?

I don't think that's important in this question (unless you are just asking for extra info)

 

[AAnsarii]

Help in this one
http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w04_qp_1.pdf
question 1,11 and 34
Thnx in advance

1-C, they slow down as liquid molecules have a lesser speed, n closer 2gether coz it looks sensible--same amt of substance will tk lesser space in liquid state than gas
11-A, mass increases, so sth must b added, when u heat Cu, u get CuO, increase in no. of atoms=increase in mass
34-B, rainwater, pH=4(acidic), passed thru CaCO3, base, n even pH increases, so that shows dat it's neutralized
hp it hlpd

 

[AAnsarii]

I don't think that's important in this question (unless you are just asking for extra info)

xtra info wont harm?

 

[AAnsarii]

ne particularly uncomprehendable n difficult qns? plz post quickly so i wont encounter a headache in d xam 2morrow, i want 2 sleep

 

[Maz]

xtra info wont harm?

Well, it's phosphoric acid.

 

[Rahma Abdelrahman]

for 1 decreases , but for the rest, i guess they all increase :3

As AAnsarii said, it increases as the size of the atom increases, but for G 1 i guess there is an exception for K as it does not follow a trend!

 

[AAnsarii]

As AAnsarii said, it increases as the size of the atom increases, but for G 1 i guess there is an exception for K as it does not follow a trend!

thx n sorry