<Tr> <Td> ChemSpider </Td> <Td> <Ul> <Li> 518 </Li> </Ul> </Td> </Tr> <Ul> <Li> 518 </Li> </Ul> <Tr> <Td> ECHA InfoCard </Td> <Td> 100.029. 071 </Td> </Tr> <Tr> <Td> KEGG </Td> <Td> <Ul> <Li> C01528 </Li> </Ul> </Td> </Tr>

How many bonds does se form in the compound h2se