Question

Which of the following reactions sumps up the photosynthetic reaction more accurately?
A.\[CO + {H_2}O \to C{H_2}O + {O_2}\]
B.\[6C{O_2} + 6{H_2}O \to {C_6}{H_{12}}{O_6} + 6{O_2}\]
C.\[6C{O_2} + 12{H_2}O \to {C_6}{H_{12}}{O_6} + 6{O_2} + {H_2}O\]
D.\[6C{O_2} + 12{H_2}O\xrightarrow[{Chlorophyll}]{{Light}}{C_6}{H_{12}}{O_6} + 6{O_2} + {H_2}O\]

Answer 1

Hint: Photosynthesis is the mechanism of plants to synthesize food for their metabolic activities. Plants use carbon dioxide from the atmosphere and water from the soil to complete its process of food production.

Complete answer:
Photosynthesis is an anabolic process through which plants convert light energy into chemical energy using their own cellular machinery.
Since, we know that plants synthesize their food using water and carbon dioxide from the atmosphere and give products as glucose and oxygen.
So, the correct option is B.
\[6C{O_2} + 6{H_2}O \to {C_6}{H_{12}}{O_6} + 6{O_2}\]
Hence, this is our complete balanced equation.
So, six molecules of carbon dioxide and six molecules of water are used to produce one molecule of glucose and six molecules of oxygen.
One most important point to keep in mind is that the oxygen produced here is not from the oxygen of carbon – dioxide but it is from the water molecules. So, oxygen is liberated from the water molecule.
All the other options have problems with the stoichiometric coefficients i.e. they have the wrong number of atoms or either the product and reactant is not correct.

Therefore, the correct option is B.

Note:
One common question that arises often is: can all the living organisms undergo photosynthesis. So, the answer is no. Only plants, algae and certain bacteria like cyanobacteria have the capability to produce their own food through photosynthesis. And such organisms who can produce their own food are known as autotrophs as they contain chlorophyll molecules. Presence of chlorophyll molecules is also one of the important factors in the process of photosynthesis to take place.