Question

a 0.24 g sample of compound of oxygen and boron was found by analysis to contain 0.096g of boron and 0.1444g of oxygen. calculate the % composition of compound by wieght.

help.... medal...

Answer 1

there's something not quite right about the question

Answer 2

% composition of compound by weight doesnt make sense to me

Answer 3

hmnm.. ya.. its 0.144g of oxygen

Answer 4

can you send me a screen shot of the question?

Answer 5

so - this is a simple calculation of %

total compound weight is 0.24g
weight of Oxygen is 0.144g

what % of 0.24 is 0.144?

for Boron
weight of Boronis 0.096g

what % of 0.24 is 0.096?

Answer 6

it could simply be Boron .096/.24 x 100 % and the same method for O2

Answer 7

Like Mr Nood has done

Answer 8

and perl

Answer 9

@perl It is not allowed by CoC of the site to give answers.

The method was described above. You should let the OP DO some work for themselves

Answer 10

I gave the calculation, not the answer

Answer 11

but i will remove it :)

Answer 12

once the numbers are in the formula it requires no thought from the OP to solve.

Answer 13

ok.. thnx ppl... can u plzz help me wid othr q n a

Answer 14

so.. nxt one,
when 3g of carbon is burnt in 8g of oxygen 11g of carbon di oxide is produced. find the mass of carbon di oxide produced on burning 3g of carbon in 50g of oxygen.

Answer 15

i would first make a balanced equation

Answer 16

first balance the equation
C + O -> CO2

Answer 17

Sorry I cant help :( Gooduck to everyone trying to figure it out though!

Answer 18

ok..... :( plzz.. .any1...

Answer 19

I THINK (but you need to check!)
Since in th efirst case the resultant mass of CO2 + 3+8 it means that ALL the Carbon and ALL the oxygen are combined in the CO2

SO
if you add MORE oxygen there is no mor carbon left to combine - so you cannot make MORE CO2 than in the first case.....

Answer 20

ok........

Answer 21

just
i am triying

Answer 22

so nxt 1...
1)if the valency of an element A is 3, write the chemical formula of its oxide.
2)if an element X has valency 2, then write the chemical formulation of potassium salt.
3)write the valency of potassium ion, and write the chemical formula of chemical phosphate.

Answer 23

so what is the valency of oxygen

Answer 24

u there

Answer 25

no 2

Answer 26

ok

Answer 27

so we just transfer the valency of both

Answer 28

.... thn.....

Answer 29

u say

Answer 30

then we have X2O3

Answer 31

idk

Answer 32

okay we have X 2 O 3

Answer 33

k..

Answer 34

then next one u try it

Answer 35

i dont know yaar.. plzz do it for me.. plzz

Answer 36

nah but u try it once

Answer 37

i dont actually know yaa

Answer 38

what is the valency of potassium

Answer 39

search it and say

Answer 40

i guess 1

Answer 41

yes then what is the valency of X

Answer 42

2

Answer 43

yes so exchange them

Answer 44

ok..
so, 1X & 2K

Answer 45

nah ur correct but we write it as X small 1 and K small 2

Answer 46

ok..

Answer 47

1and 2 are small

Answer 48

i hav still many questions to ask....

Answer 49

compute the no. of sodium ions present in 5.85g of sodium chloride.

Answer 50

wait wait I need some reaserch

Answer 51

ok..

Answer 52

So, in 1 g of NaCl, number of sodium ions= 6.023* 1023 / 58.5. So in 5.85 g of NaCl, number of sodium ions= ...

Answer 53

calculate now

Answer 54

u can do it now :)