Verified answer

You won't see very much at all, I'm afraid.

The total phase of the eclipse will be over before the Moon rises and the partial phase will end at 4:18 pm which is just about the time the Moon rises as seen from Cornwall.

If you have a completely clear horizon to the north east, you might just see some penumbral shading towards the top of the Moon, but this will have disappeared by about 4:40 and all you will see is a normal Full Moon.

PS.

sageofstars has given you the correct times, but his description is of a completely different eclipse.

You will be able to see the partial and total portions. Penumbral is not very obvious. It will rise in eclipse there and it will be very low in the south east. If you see it, it will rise in totality and you will see the shadow of the Earth slowly moving off of the Moon as time progresses.

Moonrise in the United Kingdom ranges from 21:09 BST (British Summer Time) in the Channel Islands through to 22:23 BST in the Shetland Islands. As mid-eclipse takes place at 21:12.6 BST and the end of totality at 22:03.0 BST, observers in the southernmost parts of the United Kingdom can expect to see no more than 54 of the 101 minutes of totality, decreasing the further north you travel. Much of the eclipse will take place in the south-eastern part of the sky at an altitude of less than 5° so a clear view of this horizon is vital.

Penumbral Eclipse Begins: 11:33:32 UT

Partial Eclipse Begins: 12:45:42 UT

Total Eclipse Begins: 14:06:16 UT

Greatest Eclipse: 14:31:49 UT

Total Eclipse Ends: 14:57:24 UT

Partial Eclipse Ends: 16:17:58 UT

Penumbral Eclipse Ends: 17:30:00 UT

1) Please consider posting at a more appropriate forum; I suggest Homework Help under the category Education & Reference. ^

2) Consider explaining what you've tried so far and where exactly you're getting stuck and people will help you through.