This great double portrait was painted when the artist, at the peak of his powers, had become the standard-bearer of French Neoclassicism. Lavoisier is known for his pioneering studies of oxygen, gunpowder, and the chemical composition of water. In 1789 he published a treatise on chemistry illustrated by his wife, who is believed to have been David's pupil. For political reasons, Lavoisier was obliged to withdraw the present painting from the 1789 Salon. Despite his service to the revolutionary regime, he was guillotined. (http://curiator.com/art/jacques-louis-david/antoine-laurent-lavoisier-1743-1794-and-his-wife-marie-anne-pierrette-)