Electrum protocol doubts

[readyrocky]

Hi.

Some Electrum/Stratum requests are not explained at the Electrum documentation,
it would be awesome if someone clarifies:

• blockchain.address.get_proof: (what are proofs?)
• blockchain.address.get_mempool
• blockchain.block.get_chunk: (what are chunks? are they different from headers?)
• What is the utxo_root inside the block headers. I couldn't find it on the Bitcoin protocol wiki.

thanks.