Question

(before the reaction) and the chemicals on the right side (after the reaction)
word equation
light
light is written along the arrow

Explanation:

Answer:

This appears to be the word equation for photosynthesis. The reactants (left side) are Carbon Dioxide and Water, and the products (right side) are Glucose and Oxygen. So filling in the blanks:
First blank (red, reactant): Carbon Dioxide
Second blank (red, reactant): Water
Third blank (blue, product): Glucose
Fourth blank (blue, product): Oxygen

In equation form (word equation):
Carbon Dioxide + Water $\xrightarrow{\text{Light}}$ Glucose + Oxygen