Question

why is mercury not used in a barometer

Answer 1

A barometer using water, for instance, would need to be 13.6 times taller than a mercury barometer to obtain the same pressure difference. This is because mercury is 13.6 times more dense than water. In an open-tube manometer, one end of the tube is open to the atmosphere, and is thus at atmospheric pressure.

Answer 2

Answer:

ᴀ ʙᴀʀᴏᴍᴇᴛᴇʀ ᴜsɪɴɢ ᴡᴀᴛᴇʀ, ғᴏʀ ɪɴsᴛᴀɴᴄᴇ, ᴡᴏᴜʟᴅ ɴᴇᴇᴅ ᴛᴏ ʙᴇ 13.6 ᴛɪᴍᴇs ᴛᴀʟʟᴇʀ ᴛʜᴀɴ ᴀ ᴍᴇʀᴄᴜʀʏ ʙᴀʀᴏᴍᴇᴛᴇʀ ᴛᴏ ᴏʙᴛᴀɪɴ ᴛʜᴇ sᴀᴍᴇ ᴘʀᴇssᴜʀᴇ ᴅɪғғᴇʀᴇɴᴄᴇ. ᴛʜɪs ɪs ʙᴇᴄᴀᴜsᴇ ᴍᴇʀᴄᴜʀʏ ɪs 13.6 ᴛɪᴍᴇs ᴍᴏʀᴇ ᴅᴇɴsᴇ ᴛʜᴀɴ ᴡᴀᴛᴇʀ.

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