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Ag+ (aq) + Cl- (aq) -> AgCl (s)

in a double displacement reaction

2) could be

Zn + Ag+ -> Ag + Zn 2+

The zinc displaces the silver.

i'm sure about the second one, my first one could be wrong

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Its common oxidation state is +2... Its not +1...Adahshan said:i understood the second one, But why does zinc need to be 2+, why not just 1+???

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howz all u r preparation check this might be useful viewtopic.php?f=24&t=9387

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http://www.xtremepapers.me/CIE/Cambridge IGCSE/0620 - Chemistry/0620_s09_qp_3.pdf

Q)5 b

i don't get it at all

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Assalamoalaikum!!narutogirl said:

http://www.xtremepapers.me/CIE/Cambridge IGCSE/0620 - Chemistry/0620_s09_qp_3.pdf

Q)5 b

i don't get it at all

check this out

if this doesn't help or if u have doubt let me knowxIshtar said:I have seen many people ask about Question 5.b)

So, I thought I would explain it to everyone here

From the graph, 8cm^3 of the Phosphate reacts fully with 12cm^3 of T Nitrate.

So, identifying only the atoms we need:

T : Phosphate

Taking a ratio of volumes:

8 : 12

Multiply to find the LCM of both sides.

3T : 2 Phosphate

=> Equal volumes:

24 : 24.

This implies that the formula is T3(PO4)2

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thanks but..in my graph the 8 cm^3 of phosphate stop reacting at 16 not 12 cm^3..so :SMath_angel said:Assalamoalaikum!!narutogirl said:

http://www.xtremepapers.me/CIE/Cambridge IGCSE/0620 - Chemistry/0620_s09_qp_3.pdf

Q)5 b

i don't get it at all

check this out

if this doesn't help or if u have doubt let me knowxIshtar said:I have seen many people ask about Question 5.b)

So, I thought I would explain it to everyone here

From the graph, 8cm^3 of the Phosphate reacts fully with 12cm^3 of T Nitrate.

So, identifying only the atoms we need:

T : Phosphate

Taking a ratio of volumes:

8 : 12

Multiply to find the LCM of both sides.

3T : 2 Phosphate

=> Equal volumes:

24 : 24.

This implies that the formula is T3(PO4)2

n how is the is the LCM 3:2 i guess its the oppiste and then he/she cross multiplied

umm and from where is the equal volume, and y is it mentioned?

sorry :S

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well read the question carefully

16 what u r saying is the height of precipitate! we're adding diff. volumes of sodium phosphate to find out how much is required exactly...so that is 8cm3

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i got it now..if i have only used my brain into thinking actually into just reading

umm but what did he/she mean by equal volume 24=24 ?

and thanks a lot ^__^

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before that, till 3T : 2PO4 u understood right?

that means for every 3 T we need 2 PO4

valency of PO4 is 3-

so formula is gonna be smthng like T3(PO4)x and this x we found it as 2...bcoz we just came to conclusion that 3 T requires 2 PO4 !!

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would've taken me forever to understand that i have to read the question and not just look and say omg omg omg

lol...thnx again