Question

in addition to water and carbon dioxide what two things are required for photosynthesis

Answer 1

Photosynthesis:
\(\sf\Large 6CO_2+6H_2O ~~\underrightarrow{sunlight}~C_6H_{12}O_6+6O_2\)

Answer 2

for the reaction itself only light, carbon dioxide and water are needed. but for the reaction to occur the plant also needs chlorophyll, a pigment that absorbs light and transfers light energy.