Doubt on chemistry

[Uranium-238]

I want to knw whether the thermal stabilities of the metal carbontes decreases or increases down the group....it is supposed to decrease because of the increasing cationic size so they r less distorted and less energy is required to break them down....if its not then whats the proper answer!!!!

 

[Meshuggah]

Increases down the group,
as we move down the group, the electronegativity of the cation decreases so its power to disintegrate the anion (carbonate group) decreases. Thus the stability of the metal carbonate increases and BP increases too.

 

[Uranium-238]

Increases down the group,
as we move down the group, the electronegativity of the cation decreases so its power to disintegrate the anion (carbonate group) decreases. Thus the stability of the metal carbonate increases and BP increases too.

thanks for the help!!!

 

[intel1993]

theremal stabilityb increases down the grup...as the cation size increases down the group due to which polarizing power decreases due to decrease in charge density....so cation less able to distorn anion cloud....so more stable to break....

 

[Uranium-238]

theremal stabilityb increases down the grup...as the cation size increases down the group due to which polarizing power decreases due to decrease in charge density....so cation less able to distorn anion cloud....so more stable to break....

Not exactly, because a covalent compounds usually have higher melting point than ionic...if the polarising ability decreases the compund appears to be more ionic in nature...lets say Mgcl2 is more stable than CaCl2....but for carbonates the principle is completely different..i.e. the bonding depends on charge and size so Mgco3 is stongly bonded but during decomposition the Mg0 is much more stable which means much more exothermic...In this way it is less stable compared to others down the group!!! "VIP point"

 

[hamizahmed]

 

[K.I.]

woah woah what??!
covalent compounds have HIGHER mp's than ionic? hahahah dude uv got ur basics wrong.. since when does water(ice) melt at a higher temp than MgO?

 

[beacon_of_light]

No,
Giant molecular structures like CCl4 and SiO2 have high melting points,,,otherwise ionic comppounds have higher melting points always...

 

[beacon_of_light]

No,
Giant molecular structures like CCl4 and SiO2 have high melting points,,,otherwise ionic comppounds have higher melting points always...

 

[mista.lova.lova]

woah woah what??!
covalent compounds have HIGHER mp's than ionic? hahahah dude uv got ur basics wrong.. since when does water(ice) melt at a higher temp than MgO?

what u r thinking is simple covalane molecular compunds like water!!
ever heard of SiO2 and diamond...?? they hav high m.p than MgO ..

 

[intel1993]

theremal stabilityb increases down the grup...as the cation size increases down the group due to which polarizing power decreases due to decrease in charge density....so cation less able to distorn anion cloud....so more stable to break....

Not exactly, because a covalent compounds usually have higher melting point than ionic...if the polarising ability decreases the compund appears to be more ionic in nature...lets say Mgcl2 is more stable than CaCl2....but for carbonates the principle is completely different..i.e. the bonding depends on charge and size so Mgco3 is stongly bonded but during decomposition the Mg0 is much more stable which means much more exothermic...In this way it is less stable compared to others down the group!!! "VIP point"

hey buddy ionic compunds are more stronger than covalent bonds................hence they have high mp.....n btw CaCo3 is more stable than magnesium carbonate as the thermal stability increses down the grup..........the logic behind that is the down the the group cation size increses while the charge remains unchanged, the charge density decreases hence polarizing power decreases..the anion electron cloud is less polarized and more stable to heat....................

 

[Uranium-238]

theremal stabilityb increases down the grup...as the cation size increases down the group due to which polarizing power decreases due to decrease in charge density....so cation less able to distorn anion cloud....so more stable to break....

Not exactly, because a covalent compounds usually have higher melting point than ionic...if the polarising ability decreases the compund appears to be more ionic in nature...lets say Mgcl2 is more stable than CaCl2....but for carbonates the principle is completely different..i.e. the bonding depends on charge and size so Mgco3 is stongly bonded but during decomposition the Mg0 is much more stable which means much more exothermic...In this way it is less stable compared to others down the group!!! "VIP point"

hey buddy ionic compunds are more stronger than covalent bonds................hence they have high mp.....n btw CaCo3 is more stable than magnesium carbonate as the thermal stability increses down the grup..........the logic behind that is the down the the group cation size increses while the charge remains unchanged, the charge density decreases hence polarizing power decreases..the anion electron cloud is less polarized and more stable to heat....................

Sorry to mention that its not melting point...its about "thermal stability" but the point which i gave is exact from the book and in more detail....."ADVANCED CHEMISTRY written by PHILLIP MATHEWS" check it out!!!

 

[K.I.]

no umm "mista.lova"
as any person with even half a brain would notice, the post above clearly says "a covalent compound usually has a higher mp.."
it doesnt specify being directed towards giant covalent compounds.

 

[Hamza zahid]

ANY predictionz??????????

 

[TheOne.]

hey can someone quickly explain whats dipole dipole interactions and whats induced dipole?
also please explain diative covalent bond.

 

[Jazib]

hey can someone quickly explain whats dipole dipole interactions and whats induced dipole?
also please explain diative covalent bond.

dipole dipole interactions exist b/w two same atoms, e.g in Cl2. when electrons are orbiting, at any instant, there may b a positive n negative charge "induced" in the atom, same goes with other atom, so a temperary force is induced b/w these two atoms (wish i cud make a diagram here)
in normal covalent bond, both atoms share 1,2 or 3 of there electrons. n they bind together with this bond
but in dative bond both electrons are brought by 1 atom alone, n it shares with the other atom, (it must have a lone pair to do so)