Question

ubstance.
a)
Why has this black substance formed ?​

Answer 1

Answer:

Answer. 1) The black coloursubstance is formed by the reaction of copper with oxygen. 2) The blackcolour substance is CuO or copper oxide.

Answer 2

Answer:

ᴛʜᴇ ᴛᴀɴɢɪʙʟᴇ sᴜʙsᴛᴀɴᴄᴇ ᴛʜᴀᴛ ɢᴏᴇs ɪɴᴛᴏ ᴛʜᴇ ᴍᴀᴋᴇᴜᴘ ᴏғ ᴀ ᴘʜʏsɪᴄᴀʟ ᴏʙᴊᴇᴄᴛ; "ᴄᴏᴀʟ ɪs ᴀ ʜᴀʀᴅ ʙʟᴀᴄᴋ ᴍᴀᴛᴇʀɪᴀʟ"; "ᴡʜᴇᴀᴛ ɪs ᴛʜᴇ sᴛᴜғғ ᴛʜᴇʏ ᴜsᴇ ᴛᴏ ᴍᴀᴋᴇ ʙʀᴇᴀᴅ" ᴘʜʟᴏɢɪsᴛᴏɴ - ᴀ ʜʏᴘᴏᴛʜᴇᴛɪᴄᴀʟ sᴜʙsᴛᴀɴᴄᴇ ᴏɴᴄᴇ ʙᴇʟɪᴇᴠᴇᴅ ᴛᴏ ʙᴇ ᴘʀᴇsᴇɴᴛ ɪɴ ᴀʟʟ ᴄᴏᴍʙᴜsᴛɪʙʟᴇ ᴍᴀᴛᴇʀɪᴀʟs ᴀɴᴅ ᴛᴏ ʙᴇ ʀᴇʟᴇᴀsᴇᴅ ᴅᴜʀɪɴɢ ʙᴜʀɴɪɴɢ.

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