Final answer:
The molecule made up of two atoms of an element with seven protons and three atoms of an element in group 16, period 2 is H2SO3 (sulfurous acid).
Step-by-step explanation:
A molecule made up of two atoms of an element with seven protons and three atoms of an element in group 16, period 2 is H2SO3 (sulfurous acid).
In this molecule, the element with seven protons is nitrogen (N), and the element in group 16, period 2 is sulfur (S). The molecule has two hydrogen atoms (H2), one nitrogen atom (N), and three oxygen atoms (O).
H2SO3 is a weak acid and is commonly found in solution or as a gas.