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The Avogadro constant is 6.0 x 1023 mol–1.
The number of atoms in1 mol of dinitrogen tetroxide, N2O4, is
A 3.6 × 1024
B 1.8 × 1024
C 6.0 × 1023
D 1.0 × 1023

Spoiler

Are you sure it's not A? Cus I've also got A.. 6 atoms and cos it's 1 mol, the avogadro constant should stay the same, so

Unparseable latex formula:

6 \times 6.0 \times 10 ^2^3

Reply 2941

FluffyCherry

In the mark scheme, why is there 2 different ways of calculating percentage error? eg. if it's

\pm 0.5

u'll have to multiple by

2

I guess? then divide by

100

Reply 2942

Shadowfire123

Original post by FluffyCherry

In the mark scheme, why is there 2 different ways of calculating percentage error? eg. if it's

\pm 0.5

u'll have to multiple by

2

I guess? then divide by

100

hi the question is wrong it june 2013 question 7 edexcel paper

Reply 2943

Shadowfire123

Original post by FluffyCherry

Are you sure it's not A? Cus I've also got A.. 6 atoms and cos it's 1 mol, the avogadro constant should stay the same, so

Unparseable latex formula:

6 \times 6.0 \times 10 ^2^3

yes it is A

Reply 2944

Shadowfire123

Original post by FluffyCherry

In the mark scheme, why is there 2 different ways of calculating percentage error? eg. if it's

\pm 0.5

u'll have to multiple by

2

I guess? then divide by

100

can tell me the question because I always get those question wrong

Reply 2945

FluffyCherry

Original post by Shadowfire123

can tell me the question because I always get those question wrong

It's in the edexcel MAY 2013 paper, question 21 (c)

Reply 2946

FluffyCherry

When 0.1 mol of atoms of an element reacts with chlorine,?there is an increase in mass of 7.1 g. please explain the element could be: carbon sodium magnesium aluminium

Reply 2947

Shadowfire123

Original post by FluffyCherry

It's in the edexcel MAY 2013 paper, question 21 (c)

how would you work it out

Reply 2948

Shadowfire123

Original post by FluffyCherry

When 0.1 mol of atoms of an element reacts with chlorine,?there is an increase in mass of 7.1 g. please explain the element could be: carbon sodium magnesium aluminium

you do 7.1 over 35.5 which gives you 0.2 mol this mean that its 1 -2 ratio between the element and chlorine now find which one it is

Spoiler

(edited 8 years ago)

Reply 2949

Dinaa

Original post by Shadowfire123

you do 7.1 over 35.5 which gives you 0.2 mol this mean that its 1 -2 ratio between the element and chlorine now find which one it is

Spoiler

Hey could you explain to me cis trana isomerism. idk how to look at it. The bottom and top or the left hand side to right hand side

Reply 2950

Dinaa

I said bring the tube lower and have the tube go directly into the tube.. idk and another point?

Reply 2951

FluffyCherry

Original post by Shadowfire123

how would you work it out

0.5 x 2 x 100.

you times 100 because in the question it says plus or minus 0.5.
Then divide by 11, cus of the temperature rise, which is also mentioned in the question.

Reply 2952

FluffyCherry

Original post by Dinaa

I said bring the tube lower and have the tube go directly into the tube.. idk and another point?

Do u have the markscheme?

Reply 2953

FluffyCherry

Could anyone list the calculations for unit 1 (edexcel)

Reply 2954

Shadowfire123

Original post by Dinaa

Hey could you explain to me cis trana isomerism. idk how to look at it. The bottom and top or the left hand side to right hand side

cis is like scissors they are together on one side
and trans is when they are different side

Reply 2955

Shadowfire123

Original post by FluffyCherry

0.5 x 2 x 100.

you times 100 because in the question it says plus or minus 0.5.
Then divide by 11, cus of the temperature rise, which is also mentioned in the question.