Chemistry: Post your doubts here!

[Xtreamer]

To identify SO 2 gas
http://www.gcsescience.com/itestsulphurdioxide.htm

other gases
http://www.docbrown.info/page13/ChemicalTests/ChemicalTestsg.htm

 

[Mathemagical]

Only 1 is correct.

How? When ethanoic acid has only 2 carbon atoms??

Ethanoic acid forms CH3COO- ions, whereas calcium forms Ca2+ ions. Therefore, one mole of calcium ions combines with two moles of ethanoate ions.

 

[Mathemagical]

How is this C?

Radicals can be formed on the CH3 group on the far left, on the CH2 part beside it and either one of the three CH3 groups on the right.

 

[phanttasy]

need help on this!

How many moles of nitrogen,N are in 0.65mole of (NH4)2CO3? How many grams of this compound supply this much nitrogen?

 

[princess Anu]

need help on this!

How many moles of nitrogen,N are in 0.65mole of (NH4)2CO3? How many grams of this compound supply this much nitrogen?

1 mol of (NH4)2CO3 has 2 moles of nitrogen atoms so O.65 moles will have 1.3 moles of nitrogen ATOMS
and O.65* (14*2+ 8+12+16*3) = 62.4 g of this compound give us 1.3 moles of nitrogen atoms...

This is what I think.. Lets c what others say

 

[Mathemagical]

1 mol of (NH4)2CO3 has 2 moles of nitrogen atoms so O.65 moles will have 1.3 moles of nitrogen ATOMS
and O.65* (14*2+ 8+12+16*3) = 62.4 g of this compound give us 1.3 moles of nitrogen atoms...

This is what I think.. Lets c what others say

That's correct

 

[princess Anu]

Q1; How many isomeric esters, including structural isomers and stereoisomers, can be made with the molecular formula C5H10O2, if methanoic acid is one of the two reactants... I got 4 isomers.. is that correct? options include 2,3,4 & 5


Q2; How many isomers, including structural and stereoisomers, with the formula C4 H8 have structures that include Pi bonding.. I got 4 isomers.. is that correct? options include 1, 2,3 &4

 

[Mathemagical]

Q1; How many isomeric esters, including structural isomers and stereoisomers, can be made with the molecular formula C5H10O2, if methanoic acid is one of the two reactants... I got 4 isomers.. is that correct? options include 2,3,4 & 5


Q2; How many isomers, including structural and stereoisomers, with the formula C4 H8 have structures that include Pi bonding.. I got 4 isomers.. is that correct? options include 1, 2,3 &4

Yes, I got 4 isomers each too.

 

[princess Anu]

Yes, I got 4 isomers each too.

What about alcoholic isomers, including stereo & structural, for C4H10O
I get 4 again options are 3,4,5,6

 

[Mathemagical]

What about alcoholic isomers, including stereo & structural, for C4H10O
I get 4 again options are 3,4,5,6

Yes, I got 4 again too.

 

[princess Anu]

help

 

[Mathemagical]

help

Mr(P) = 31
Mr(P2O5) = 2(31) + 5(16) = 142
In 100 g of fertiliser, there is 30.0% P2O5
That means mass of fertiliser is
= (100/30) * Mr(P2O5)
= (100/30) * 142
= 473.3 g

% of phosphorus in fertiliser is
= (2*31 / 473.3) * 100
= 13.1 %

 

[princess Anu]

Q38..

 

[princess Anu]

..

 

[Autumn98]

if the ans is B..

Thankyou so muuch!

 

[Mathemagical]

..View attachment 54408

If all monomers combine, one molecule of the polymer is formed, which is 1/6.02*10^23 moles. The theoretical range is between 1 and 1/6.02*10^23, but it cannot be 1.

 

[qwertypoiu]

Q38..

Is it A?

 

[Choi WW]

The answer is A

I believe that phosphoric acid is a weak acid, so is the phosphorous acid strong acid?

 

[nehaoscar]

??

 

[nehaoscar]

Mg + 2H2O = Mg(OH)2 + H2

Mg (24.3) + O (16+16) + H (1+1) = 58.3 Mr ... so shouldn't A be wrong?

But then it's D ... is it slightly soluble then?