Both teams on University Challenge were caught out by this tricky question - but can you solve it?
Some of the brightest brains in the country were brought together and put to the test on the iconic quiz show, which aired on Monday evening (September 2).
The BBC programme pits the UK's top universities against each other in an intellectual showdown to crown the smartest institution. In the latest episode, teams from the University of Warwick and the University of East Anglia prepared to face their first starter for ten.
But just minutes into the programme, both teams struggled to answer the question asked by presenter Amol Rajan. Are you ready to have a go?
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He asked: "Used to detect the presence of lipids, what test involves first dissolving a sample in ethanol before mixing this with water, A positive result for the presence of lipids is indicated by the formation of a milky white lipid?"
Saha, from team UEA, buzzed in first and answered Benedict's test. This is a chemical test that can be used to check for the presence of reducing sugars in a given analyte, and was therefore the wrong answer.
Turning to Warwick, Hart suggested Tollens' test. Also known as silver-mirror test, Tollens' test is a qualitative laboratory test used to distinguish between an aldehyde and a ketone.
Rajan shattered Warwick's hopes of gaining points as he confirmed this was the wrong answer. But don't worry, the answer is coming up shortly, so if you're still mulling it over, try not to scroll down too far.
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The correct answer was emulsion test.
Did you manage to crack it? Share your thoughts in the comments section below.
Elsewhere in the episode, BBC viewers issued a stern warning to one of the show's contestants, Thomas Hart. The maths student from South Wales studying at the University of Warwick, caught the attention of fans due to his unique habit.
The student seemed excited to be on the gameshow and held his elbow up high with his hand always suspended on the buzzer while the show progressed. He then proceeded to slam the buzzer with a lot of passion, sometimes pressing it several times to sure he had pressed it properly.
“Calm down Hart! You'll break either the buzzer or your thumb!” warned one person on X. Another penned: "Do you think Hart has to have physio on that elbow after the match? Or even worse, worked out and trained for it?"
