A woman was fatally splashed with acid after visiting her daughter's grave when she unwittingly got caught up in an argument, a court heard.
Joanne Rand died 11 days after being splashed while sitting on a bench in Frogmoor, High Wycombe, on 3 June.
Reading Crown Court heard Xeneral Webster took the acid from his bag while arguing with another man who knocked the bottle out of his hand, splashing Ms Rand, 47.
Mr Webster, 19, denies her murder.
The court heard Ms Rand was splashed head to toe with acid.
She screamed in pain and ran to a nearby KFC restaurant to douse herself with water.
Ms Rand was treated in hospital and was discharged before being readmitted.
She died on 14 June from multi-organ failure after contracting septicaemia due to the acid burns.
Prosecutor Alison Hunter QC said CCTV footage showed Mr Webster "producing an open-topped bottle of acid", telling the other man he was arguing with, Saqib Hussain, "this is acid".
"At this moment Mr Hussain, panicking, knocks the acid out of Mr Webster's hand," Ms Hunter said.
The court heard the bottle then rolled and hit Ms Rand who was sitting a few metres away.
Ms Hunter said it "makes no difference" Ms Rand was not Mr Webster's intended victim as he knew the consequences of having acid in public, having been the victim of an acid attack himself.
Mr Webster admitted being involved in an altercation, which he said was about drugs, but denied possessing the bottle of acid, the jury was told.
Mr Webster, of Banstead Court, Westway, west London, denies six charges dated between April and June last year.
He faces a murder charge and an alternative count of manslaughter, possessing a bottle of acid, possessing a bottle of ammonia, attempted GBH with intent and robbery of a bicycle.
The trial continues.