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Elemental sulfur commonly occurs in form of $\ce{S8}$, with relatively low melting point and, more importantly, relatively low bond energies. So, it easily breaks.

Carbon commonly occurs as graphite or structures composed of graphite-like fragments, but usually something we call carbon contains up to 10% of other elements, meaning it can produce some combustible gases on heating.

However, more importantly, both elements mentioned above produce gaseous oxides on oxidation, that leave the surface of the reacting compound, exposing it to further reaction.

Silicon, on the other hand, produces solid oxide on heating, that prevents further reaction. It is still possible to make a very fine dust of silicon to react with oxigen, but it is not an easy feat. For reaction to occur to bulk silicon, the products must be removed from the surface. Given that, bulk silicon will not give silicon oxide, but it can react with chlorine in reasonable conditions, giving volatile silicon tetrachloride.

Why silicon forms solid oxide with high melting point is another matter, with answer considerably more obscure. The simplest approach to retionalize it would be to consider atomic radius of carbon, sulfur and silicon and consider bonding in alternative structures for this compounds.

Carbon dioxide is an oxide with small central atom, that can form $\pi$-bonds effectively with oxige, so it does not form polymeric structure.

Sulfur dioxide is an oxide of larger atom, but it has a lone pair on central atom, so polimeric form would be considerably hindered. (on contrary, sulfur trioxide forms polimeric forms, but still has gaseous form which is only marginally less stable).

Silicon dioxide in monomeric form has two $\pi$-bonds, and this is uncharacteristic for third row elements, and silicon is significanly larger than carbon, having enough space for four oxigens around it. So, it easily and effectively forms 3-d network of $\ce{SiO4}$ units with shared oxigens, that is quite hard to melt and vaporise, and, once formed on the surface of silicon, it prevents further reaction.

Still, formation of silicon dioxide films on surface of bulk monocristalline silicon is essential for microelectronics.

Elemental sulfur commonly occurs in form of $\ce{S8}$, with relatively low melting point and, more importantly, relatively low bond energies. So, it easily breaks.

Carbon commonly occurs as graphite or structures composed of graphite-like fragments, but usually something we call carbon contains up to 10% of other elements, meaning it can produce some combustible gases on heating.

However, more importantly, both elements mentioned above produce gaseous oxides on oxidation, that leave the surface of the reacting compound, exposing it to further reaction.

Silicon, on the other hand, produces solid oxide on heating, that prevents further reaction. It is still possible to make a very fine dust of silicon to react with oxygen, but it is not an easy feat. For reaction to occur to bulk silicon, the products must be removed from the surface. Given that, bulk silicon will not give silicon oxide, but it can react with chlorine in reasonable conditions, giving volatile silicon tetrachloride.

Why silicon forms solid oxide with high melting point is another matter, with answer considerably more obscure. The simplest approach to rationalize it would be to consider atomic radius of carbon, sulfur and silicon and consider bonding in alternative structures for this compounds.

Carbon dioxide is an oxide with small central atom, that can form $\pi$-bonds effectively with oxide, so it does not form polymeric structure.

Sulfur dioxide is an oxide of larger atom, but it has a lone pair on central atom, so polymeric form would be considerably hindered. (on contrary, sulfur trioxide forms polymeric forms, but still has gaseous form which is only marginally less stable).

Silicon dioxide in monomeric form has two $\pi$-bonds, and this is uncharacteristic for third row elements, and silicon is significantly larger than carbon, having enough space for four oxygens around it. So, it easily and effectively forms 3-d network of $\ce{SiO4}$ units with shared oxygens, that is quite hard to melt and vaporize, and, once formed on the surface of silicon, it prevents further reaction.

Still, formation of silicon dioxide films on surface of bulk monocrystalline silicon is essential for microelectronics.

Elemental sulfur commonly occurs in form of $\ce{S8}$, with relatively low melting point and, more importantly, relatively low bond energies. So, it easily breaks.

Carbon commonly occurs as graphite or structures composed of graphite-like fragments, but usually something we call carbon contains up to 10% of other elements, meaning it can produce some combustible gases on heating.

However, more importantly, both elements mentioned above produce gaseous oxides on oxidation, that leave the surface of the reacting compound, exposing it to further reaction. Silicon, on the other hand, produces solid oxide on heating, that prevents further reaction. It is still possible to make a very fine dust of silicon to react with oxigen, but it is not an easy feat. For reaction to occur to bulk silicon, the products must be removed from the surface. Given that, bulk silicon will not give silicon oxide, but it can react with chlorine in reasonable conditions, giving volatile silicon tetrachloride.

Why silicon forms s solid oxide with high melting point is another matter, with answer considerably more obscure. The simplest approach to understand it would be to consider atomic radius of carbon, sulfur and silicon and consider bonding in alternative structures for this compounds.

Carbon dioxide is an oxide with small central atom, that can form $\pi$-bonds effectively with oxige, so it does not form polymeric structure. Sulfur dioxide is an oxide of larder atom, but it has a lone pair on central atom, so polimeric form would be considerably hindered. (on contrary, sulfur trioxide forms polimeric forms, but still has gaseous form wich is only marginally less stable). Silicon dioxide in monomeric form have two $\pi$-bonds, that are uncharacteristic for third row, and oxigen is significanly larger than carbon, easily bonding with four oxigens. So, it easily and effectively forms 3-d network of $\ce{SiO4}$ units with shared oxigens, and is quite hard to melt and vaporise, and, once formed on the surface of silicon, it prevents further reaction. Still, formation of silicon dioxide films on surface of bulk monocristalline silicon is essential for microelectronics.

Elemental sulfur commonly occurs in form of $\ce{S8}$, with relatively low melting point and, more importantly, relatively low bond energies. So, it easily breaks.

Carbon commonly occurs as graphite or structures composed of graphite-like fragments, but usually something we call carbon contains up to 10% of other elements, meaning it can produce some combustible gases on heating.

However, more importantly, both elements mentioned above produce gaseous oxides on oxidation, that leave the surface of the reacting compound, exposing it to further reaction. 

Silicon, on the other hand, produces solid oxide on heating, that prevents further reaction. It is still possible to make a very fine dust of silicon to react with oxigen, but it is not an easy feat. For reaction to occur to bulk silicon, the products must be removed from the surface. Given that, bulk silicon will not give silicon oxide, but it can react with chlorine in reasonable conditions, giving volatile silicon tetrachloride.

Why silicon forms solid oxide with high melting point is another matter, with answer considerably more obscure. The simplest approach to retionalize it would be to consider atomic radius of carbon, sulfur and silicon and consider bonding in alternative structures for this compounds.

Carbon dioxide is an oxide with small central atom, that can form $\pi$-bonds effectively with oxige, so it does not form polymeric structure. 

Sulfur dioxide is an oxide of larger atom, but it has a lone pair on central atom, so polimeric form would be considerably hindered. (on contrary, sulfur trioxide forms polimeric forms, but still has gaseous form which is only marginally less stable). 

Silicon dioxide in monomeric form has two $\pi$-bonds, and this is uncharacteristic for third row elements, and silicon is significanly larger than carbon, having enough space for four oxigens around it. So, it easily and effectively forms 3-d network of $\ce{SiO4}$ units with shared oxigens, that is quite hard to melt and vaporise, and, once formed on the surface of silicon, it prevents further reaction. 

Still, formation of silicon dioxide films on surface of bulk monocristalline silicon is essential for microelectronics.

Elemental sulfur commonly occured in form of $\ce{S8}$, with relatively low melting point and, more importantly, relatively low bond energies. So, it easily breaks.

Carbon commonly occurs as graphite or structures composed of graphite-like fragments, but usually something we call carbon contains up to 10% of other elements, meaning it can produce some combustible gases on heating.

However, more importantly, both elements mentioned above produce gaseous oxides on oxidation, that leave the surface of the reacting compound, exposing it to further reaction. Silicon, on the other hand, produces solid oxide oh heating, that prevents further reaction. It is still possible to make a very fine dust of silicon to react with oxigen, but it is not an easy feat. For reaction to occur to bulk silicon, the products must be removed from the surface. Given that, bulk silicon will not give silicon oxide, but it can react with chlorine in reasonable conditions, giving volatile silicon tetrachloride.

Why silicon forms s solid oxide with high melting point is another matter, with answer considerably more obscure. The simplest approach to understand it would be to consider atomic radius of carbon, sulfur and silicon and consider bonding in alternative structures for this compounds.

Carbon dioxide is an oxide with small central atom, that can form $\pi$-bonds effectively with oxige, so it does not form polymeric structure. Sulfur dioxide is an oxide of larder atom, but it has a lone pair on central atom, so polimeric form would be considerably hindered. (on contrary, sulfur trioxide forms polimeric forms, but still has gaseous form wich is only marginally less stable). Silicon dioxide in monomeric form have two $\pi$-bonds, that are uncharacteristic for third row, and oxigen is significanly larger than carbon, easily bonding with four oxigens. So, it easily and effectively forms 3-d network of $\ce{SiO4}$ units with shared oxigens, and is quite hard to melt and vaporise, and, once formed on the surface of silicon, it prevents further reaction. Still, formation of silicon dioxide films on surface of bulk monocristalline silicon is essential for microelectronics.

Elemental sulfur commonly occurs in form of $\ce{S8}$, with relatively low melting point and, more importantly, relatively low bond energies. So, it easily breaks.

Carbon commonly occurs as graphite or structures composed of graphite-like fragments, but usually something we call carbon contains up to 10% of other elements, meaning it can produce some combustible gases on heating.

However, more importantly, both elements mentioned above produce gaseous oxides on oxidation, that leave the surface of the reacting compound, exposing it to further reaction. Silicon, on the other hand, produces solid oxide on heating, that prevents further reaction. It is still possible to make a very fine dust of silicon to react with oxigen, but it is not an easy feat. For reaction to occur to bulk silicon, the products must be removed from the surface. Given that, bulk silicon will not give silicon oxide, but it can react with chlorine in reasonable conditions, giving volatile silicon tetrachloride.

Why silicon forms s solid oxide with high melting point is another matter, with answer considerably more obscure. The simplest approach to understand it would be to consider atomic radius of carbon, sulfur and silicon and consider bonding in alternative structures for this compounds.

Carbon dioxide is an oxide with small central atom, that can form $\pi$-bonds effectively with oxige, so it does not form polymeric structure. Sulfur dioxide is an oxide of larder atom, but it has a lone pair on central atom, so polimeric form would be considerably hindered. (on contrary, sulfur trioxide forms polimeric forms, but still has gaseous form wich is only marginally less stable). Silicon dioxide in monomeric form have two $\pi$-bonds, that are uncharacteristic for third row, and oxigen is significanly larger than carbon, easily bonding with four oxigens. So, it easily and effectively forms 3-d network of $\ce{SiO4}$ units with shared oxigens, and is quite hard to melt and vaporise, and, once formed on the surface of silicon, it prevents further reaction. Still, formation of silicon dioxide films on surface of bulk monocristalline silicon is essential for microelectronics.