Question

why water is liquid and so2 gas at room temperature

Answer 1

And there exists another type of chemical bond among others which is called hydrogen bond. Which is formed between hydrogen and these three most electronegative elements only.

Hydrogen bond is seen to be available only in compounds having these three elements (F, O, N ) making those compounds liquid in state.

So you may come to see that in H2S there does not exist a hydrogen bond but in H2O , the hydrogen bond does exist.

So because of hydrogen bond, the water (H2O) is a liquid and hydrogen sulphide (H2S) is not.

In the following picture you will see hydrogen bonding in water , which is absent in hydrogen sulphide gas.

Answer 2

ɪɴ ʜ2ᴏ ᴛʜᴇʀᴇ ɪs ʜʏᴅʀᴏɢᴇɴ ʙᴏɴᴅɪɴɢ ʙᴇᴄᴀᴜsᴇ ᴏxʏɢᴇɴ ʜᴀs ᴀ ʜɪɢʜ ᴇʟᴇᴄᴛʀᴏɴᴇɢᴀᴛɪᴠɪᴛʏ(ᴏɴʟʏ sᴇᴄᴏɴᴅ ᴛᴏ ғʟᴏᴜʀɪɴᴇ). sᴏ, ᴛʜᴇ ʜʏᴅʀᴏɢᴇɴ ᴀᴛᴏᴍs ғʀᴏᴍ ᴏᴛʜᴇʀ ᴍᴏʟᴇᴄᴜʟᴇs ᴏғ ᴡᴀᴛᴇʀ ғᴏʀᴍs ᴀ ʜʏᴅʀᴏɢᴇɴ ʙᴏɴᴅs ᴡɪᴛʜ ᴏxʏɢᴇɴ ʀᴇsᴜʟᴛɪɴɢ ɪɴ ɪɴᴛᴇʀᴍᴏʟᴇᴄᴜʟᴀʀ ʜʏᴅʀᴏɢᴇɴ ʙᴏɴᴅɪɴɢ. ... ᴛʜᴇʀᴇғᴏʀᴇ ᴀᴛ ʀᴏᴏᴍ ᴛᴇᴍᴘᴇʀᴀᴛᴜʀᴇ ʜ2ᴏ ɪs ᴀ ʟɪϙᴜɪᴅ ᴀɴᴅ ʜ2s ɪs ᴀ ɢᴀs.