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What does thermal stability depend on?

What does thermal stability depend on?

Thermal stability depends on the size of the atom and the bond strength. As the size of the atom decreases, the bond dissociation energy increases and hence, the thermal stability increases and vice-versa i.e. it is inversely proportional to the size of the atom.

What is nitrides explain their properties?

Certain metal nitrides are unstable, and most react with water to form ammonia and the oxide or hydroxide of the metal; but the nitrides of boron, vanadium, silicon, titanium, and tantalum are very refractory, resistant to chemical attack, and hard—and thus are useful as abrasives and in making crucibles. …

Why is barium carbonate more thermally stable?

The thermal stability increases as you go down Group 2. This is because the Group 2 ion has lower charge density, and thus distorts the carbonate ion less. The less distorted the carbonate ion is, the more stable it is, and so a higher temperature is required to decompose the carbonate.

Why is calcium carbonate more thermally stable than magnesium carbonate?

The positive ion attracts the delocalised electrons in the carbonate ion towards itself. The carbonate ion becomes polarised. If this is heated, the carbon dioxide breaks free to leave the metal oxide. In other words, as you go down the Group, the carbonates become more thermally stable.

What affects thermal stability?

The factors related to the polymer structure significantly affecting thermal stability are functional groups, molecular weight, branch degree, cross-linking, and crystallinity.

Which has highest thermal stability?

In salts of monatomic anion, thermal stability is directly proportional to lattice energy i.e. smaller is interatomic distance higher is the thermal stability. So BeCl2which has the smallest cation has the highest lattice energy and hence has highest thermal stability.

What are nitrides used for?

Uses of Nitride Silicon nitride and titanium nitride are used as hard coatings and cutting materials. Hexagonal boron nitride is used as a high-temperature lubricant akin to moly (molybdenum disulfide). Nitride compounds are used as insulators.

What are nitrides give it’s classification?

Nitrides are compounds of nitrogen having an oxidation state of 3-. Nitrides can be classified into three general categories: ionic, interstitial, and covalent. Alkali and alkaline earth nitrides are called as ionic nitrides. Alkaline earth nitrides are formed with the formula M3N2 (for example, Ca3N2, Ba3N2, Mg3N2).

Why does thermal stability of 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.

Which carbonate is thermally most stable?

The thermal stability (measured by the temperature of decomposition) of these carbonates increases on moving down the group due to the increase of electropositive character of the metal or basicity of the metal hyroxide. Thus, BeCO3 is least thermally stable while BaCO3 is most thermally stable.

Why do carbonates become more thermally stable down the group?

Which is more stable calcium carbonate or magnesium carbonate?

MgCO3 is thermally more stable than CaCO3 .