More than 2,500 people have signed a petition to lower grade boundaries for an 'impossible' chemistry A-level exam.

Thousands of students left their chemistry unit 4 exams confused yesterday, complaining that the questions were obscure and there was not enough time to answer them.

Many now fear their future plans as vets or doctors are in jeopardy, with one joking: 'Doesn't look like there's going to be any medic, veterinary or dentistry students this year.'

More than 2,000 people have signed a petition to lower grade boundaries for an 'impossible' chemistry A-level exam. File image

The students first set up a Facebook complaint group and it was then followed by an online petition (pictured) calling for AQA to lower the grade boundaries

Kemi Bello, from London, wrote: That paper was just ridiculous. No previous AQA Chemistry unit 4 papers could have prepared you for that exam.'

Hundreds joined a complaint group on Facebook, which criticised the 'vague' phrasing and said there were too many one and two-mark questions, followed by a 'sly' nine-mark one at the end.

The page described it as: 'An embarrassment for AQA. So many application questions, many 1-2 mark questions which were time-consuming, sly placement of a 9 marker at the end.'

The students have now created a petition encouraging AQA to lower the grade boundaries, with many claiming the paper has ruined their chances of getting into university.

More than 2,500 people have now signed the petition and hundreds have left comments on the site.

Dana Settle, from Manchester, wrote on the page: 'I am really concerned that I will now not make my entry requirements for veterinary medicine in uni.

'My hard-earned university offers (including 19 weeks of work experience) will go to waste.'

Some students posted jokes about how hard the exam was, with one joking that the solution to the difficult exam was to go into clearing, often used by students who don't get the grades to accept their offers

An anonymous student wrote: 'I couldn't have revised any more for this exam. Yet you still have ruined my chances of getting into university due to this awful paper!'

Another said: 'After achieving 95%+ in AS and going to a high-achieving grammar school, everyone came out of this exam shocked.

'It's understandable to add a few hard questions in like 2015 but this paper's whole structure and type of questions were changed with only a small percentage actually familiar!'

Another student said: 'Overall this exam was way too difficult compared to previous years and deserves lower grade requirements.'

A parent, Vanessa, from London, write: 'Daughter was distraught. What an unfair representation of the students' knowledge. '

Some students joked about how hard the paper was (top, Facebook) but others thought it had ruined their chances of going to university on the comments section of the petition (below, from the petition)

Some students posted jokes about how hard the exam was, with one joking that the solution to the difficult exam was to go into clearing, often used by students who don't get the grades to accept their offers.

However, AQA said that a decision on grade boundaries will not be made until they have seen the papers, and it will take into consideration the overall performance of students.

An AQA spokesman said: 'Exams aren’t meant to be easy and students are obviously going to talk about that on social media, but everything in the paper was on the syllabus.

'There’s no need for anyone to worry about grade boundaries because these aren’t decided until we’ve marked all the papers and know how everyone got on.