What is thermal stability of carbonates?
As we move down the group alkaline earth metal carbonates require more heating to decompose, so carbonates become more thermally stable down the group.
Why does thermal stability of metal carbonates increase down the group?
As the positive ions get larger down the group, they affect on the carbonate ions near them less. More heat must be supplied for the carbon dioxide to leave the metal oxide. In other words, the carbonates become more thermally stable down the group.
Does thermal stability increase down group?
All these carbonates decompose on heating to given CO2 and metal oxide. The thermal stability of these carbonates increases down the group i.e., from Be to Ba.
How does the thermal stability vary among carbonates of alkali metals?
From Li to Cs, thermal stability of carbonates increases. From Li to Cs, due to larger ion size, hydration enthalpy decreases. So, solubility should decrease from Li to Cs.
Do Group 1 carbonates decompose?
In Group 1, lithium carbonate behaves in the same way – producing lithium oxide and carbon dioxide. The rest of the Group 1 carbonates don’t decompose at Bunsen temperatures, although at higher temperatures they will.
Which of the following carbonates is thermally unstable?
Beryllium carbonate is thermally unstable.
Why does the stability of carbonates of Group 1 elements increase down the group?
The carbonate ion has a big ionic radius so it is easily polarized by a small, highly charged cation. Group I cations increase in ionic radius down the group. The smaller the ionic radius of the cation, the more densely charged it is. Therefore the better it is at polarizing carbonate ions.
Why does the decomposition of carbonates decrease down the group?
Explaining the relative falls in lattice enthalpy The lattice enthalpies of both carbonates and oxides fall as you go down the Group because the positive ions are getting bigger. The inter-ionic distances are increasing and so the attractions become weaker.
Which of the following carbonates show least thermal stability?
BeCO3 is least thermally stable. The thermal stability of carbonates increases down the group i.e from Be to Ba.
Which carbonates of alkali metals has highest thermal stability?
As the electropositive character increase down the group, the stability of alkali carbonates increases. Hence more thermal energy required for the decomposition of alkali carbonates down the group. Hence, Rb2CO3 have more thermal stability than others.
Why is Group 1 more thermally stable than group2?
If the positive ion only had one positive charge, the polarising effect would be less. That is why the Group 1 compounds are more thermally stable than those in Group 2. As the positive ions get bigger as you go down the Group, they have less effect on the carbonate ions near them.
Which of the carbonates given below is unstable?
Beryllium carbonate is unstable due to the smaller size of cation and larger size of anion (as smaller cation stabilizes smaller anion through crystal lattice energy) and can be kept only in the atmosphere of CO2.
How to predict the Order of thermal stability of metal carbonates?
Predict the order of thermal stability of the group 1 and 2 metal carbonates. The higher the temperature required to decompose, the more stable it will be. In group I that the thermal stability increase down the group as the polarity power decreases. Same with group 2
Why does solubility of carbonate decrease from Li to CS?
From Li to Cs, thermal stability of carbonates increases. From Li to Cs, due to larger ion size, hydration enthalpy decreases. So, solubility should decrease from Li to Cs. But, experimentally, order is reverse. I cannot wrap my head around this.
What is the thermal stability of Group 2 hydrogencarbonates?
The thermal stability of the hydrogencarbonates. The Group 2 hydrogencarbonates like calcium hydrogencarbonate are so unstable to heat that they only exist in solution. Any attempt to get them out of solution causes them to decompose to give the carbonate, carbon dioxide and water.
What is the thermal stability of oxides of Group 1 elements?
The thermal stability of most compounds of Group 1 elememts (hydroxides, carbonates, nitrates) increases down the group due to decrement in charge density of the cation. Now, according to one of my study sources, thermal stability of oxides is as follows: