The session will be held exactly two weeks before voters go to the polls.
Nicola Sturgeon will face questions from both Scottish Labour deputy leader Kezia Dugdale and Scottish Conservative leader Ruth Davidson.
Ms Sturgeon's SNP has been the focus of sustained attacks from both Labour and the Conservatives in recent days.
The Scottish Parliament will be sitting as campaigning across the country continues ahead of the UK general election on 7 May.
John Swinney, the SNP's deputy leader, will be out on the streets of Edinburgh, where he will tell voters that the election is a choice between further austerity offered by the Westminster parties and the SNP, who he will say are pledging to end austerity and to invest in jobs and public services.
Mr Swinney said: "Ending austerity is without doubt the key issue of this general election campaign - and both Labour and the Tories are on the wrong side of people in Scotland and many people across the UK.  Austerity has failed on every measure - and it's time for a new, more progressive approach."
Meanwhile, Scottish Liberal Democrat leader Willie Rennie will be joined on the election trail in Cardross, Argyll, by his son to mark Take Your Child to Work Day.
Mr Rennie will set out his party's plans for a massive expansion in free childcare for Scottish families and announce details of a families manifesto which he said would include measures to give children the best start in life.
Scottish Labour leader Jim Murphy will tell a rally in Edinburgh that Prime Minister David Cameron is "playing with fire" by overplaying the SNP's electoral chances.
He will also argue SNP plans for fiscal responsibility, formerly referred to as "fiscal autonomy", for Scotland would put state pensions at risk.
Scottish Conservatives leader Ms Davidson will also be campaigning in the capital, where she will join activists on a street stall and meet members of the public.
The Tories said the main theme of the day would be powers for the Scottish Parliament.
What are the top issues for each political party at the 2015 general election?
Policy guide: Where the parties stand
General election issues are likely to be high on the agenda as MSPs meet for the first First Minister's Questions since the Easter recess.