chemistry unit 3 !!! discussion in here !! =p

[durr]

^look in the question, somewhere he will tell you assume density is 1g/cm3, and you have 50cm3 acid, which is 50g.

 

[U stalking ME]

you guyz try this > NAHCO3 + Y UNDER HEATIN CO2 ECOLVE
STATE WAT IONS COMPOUND Y WOULD HAVE ??
HOW DO WE THINK IN THAT ??? ITS HYDROGEN BUT HOW ??

nd ya this one too plzz !
50 CM^3 OF 0.05 MOL/DM^3 OF THE ACID SOLUTION !
CALCULATE DELTA H ! =(M) (C) (DELTA T) !
NOW HOWS THE MASS 50 IN THAT FORMULA ????

NaHCO3(s) + HCL(aq) = NaCl(aq) + h20(g) + co2(g)

then we cancel out the spectator ions so we get;
NaHCO3(s) + H(ions) = Na(ions)+ h20(g) + co2(g) Thus Y has H+ (ions).

for the next one we assume that the density is 1 g/cm3. so the mass of the solution is numerically equal to its volume.

 

[DANGERBP]

NaHCO3(s) + HCL(aq) = NaCl(aq) + h20(g) + co2(g)

then we cancel out the spectator ions so we get;
NaHCO3(s) + H(ions) = Na(ions)+ h20(g) + co2(g) Thus Y has H+ (ions).

for the next one we assume that the density is 1 g/cm3. so the mass of the solution is numerically equal to its volume.

mm.. for the first one why not for example k ? potasssium ?
nd do we always assume that the density is 1 ??

hey n thx =p

 

[U stalking ME]

mm.. for the first one why not for example k ? potasssium ?
nd do we always assume that the density is 1 ??

hey n thx =p

then wont K replace Na coz its higher in the reactivity series thus giving KHCO3 + Na
yup until they mention in the question
No prob

 

[DANGERBP]

then wont K replace Na coz its higher in the reactivity series thus giving KHCO3 + Na
yup until they mention in the question
No prob

shit man ya thts true =$ ! ugh its hard thinkin like this while solvin =p
=) ya thx

 

[U stalking ME]

shit man ya thts true =$ ! ugh its hard thinkin like this while solvin =p
=) ya thx

lol true
welcome

 

[DANGERBP]

then wont K replace Na coz its higher in the reactivity series thus giving KHCO3 + Na
yup until they mention in the question
No prob

wait it could be calcium ??? anythin less reactive than na ??

 

[DANGERBP]

when CH2CHCH2OH is heated in a crucable with NA ! 3 observations r na dissapear
effervescenes gas appear ? the gas is wat ??
and white solid forms ?? wasnt it solid b4 ??

 

[DANGERBP]

hey ppl who have year 2009 june plus mark scheme ?

 

[U stalking ME]

wait it could be calcium ??? anythin less reactive than na ??

anything more reactive than Na will replace it, anything less reactive no reaction will take place. And even if we make Y one of these like K the reaction will not give us CO2.

 

[DANGERBP]

anything more reactive than Na will replace it, anything less reactive no reaction will take place. And even if we make Y one of these like K the reaction will not give us CO2.

ugh man =/ why no rxn with less reactive metals =$

 

[U stalking ME]

when CH2CHCH2OH is heated in a crucable with NA ! 3 observations r na dissapear
effervescenes gas appear ? the gas is wat ??
and white solid forms ?? wasnt it solid b4 ??

the gas is hydrogen, sodium disappears, white ppt of sodium propoxide formed

 

[DANGERBP]

the gas is hydrogen, sodium disappears, white ppt of sodium propoxide formed

thankss =p !
can u write me the equation plz =$ =p

 

[U stalking ME]

ugh man =/ why no rxn with less reactive metals =$

less reactive metal cannot replace highly reactive metals therefore no reaction takes place.

 

[U stalking ME]

thankss =p !
can u write me the equation plz =$ =p

CH3CH2CH2OH(l) + Na(s) = CH3CH2CH2O-Na+(s) + 0.5H2(g)

 

[tripleA95]

What does a dropping funnel/separating funnel look like. How do we draw it?

 

[U stalking ME]

What does a dropping funnel/separating funnel look like. How do we draw it?

 

[tripleA95]

Thank you, but listen if there's an organic substance it's on the top layer right?

 

[code11]

you guyz try this > NAHCO3 + Y UNDER HEATIN CO2 ECOLVE
STATE WAT IONS COMPOUND Y WOULD HAVE ??
HOW DO WE THINK IN THAT ??? ITS HYDROGEN BUT HOW ??

nd ya this one too plzz !
50 CM^3 OF 0.05 MOL/DM^3 OF THE ACID SOLUTION !
CALCULATE DELTA H ! =(M) (C) (DELTA T) !
NOW HOWS THE MASS 50 IN THAT FORMULA ????

density=mass/volume
so density is assumed to b 1 hence
volume *1= mass

 

[U stalking ME]

Thank you, but listen if there's an organic substance it's on the top layer right?

aqueous layer is always on the top unless they give u the density of the organic layer