Video Transcript
Which of the following is the
correct balanced symbol equation for photosynthesis?
This question presents us with four
options for chemical equations for photosynthesis that use chemical symbols. We need to choose the one that’s
correct in that the products and the reactants are in the correct places and also
ensure that the chemical equation is balanced. Meaning that there are the same
numbers of each type of atom on the left side of the arrow and on the right.
In order to answer this question,
we’re first going to recall the word equation for photosynthesis, and then we’re
gonna convert it into the correct and appropriate chemical symbols. Then, we’ll make sure that it’s
properly balanced so that we can easily choose the correct answer.
Let’s recall that photosynthesis is
a process carried out by plants, in which water absorbed through the roots from the
soil and carbon dioxide absorbed from the air through the leaves is converted using
the energy found in light into oxygen, which, luckily for us, is released into the
air through the leaves, and glucose, which is consumed by some other organisms. And the plant uses for cellular
respiration as well as the production of various other molecules.
Now, we have all the information we
need to generate our word equation, which reads carbon dioxide and water are
converted into glucose and oxygen. Now, we can replace each of these
terms with the correct chemical symbol to get the symbol equation. The chemical symbol for carbon
dioxide is CO2. The chemical symbol for water is
H2O. The chemical symbol for glucose is
C6H12O6. And the chemical symbol for oxygen
is O2.
Here, I’ve drawn the molecules in
this symbol equation to show that right now it’s not balanced. There are many more atoms of
carbon, hydrogen, and oxygen in the products than there are in the reactants. In order to make the two sides
equal, we need to add some coefficients. Luckily for us, it’s pretty easy to
remember all of the coefficients for the smaller molecules are six. Glucose is a relatively large
molecule, and there’s only one in this balanced chemical equation.
Now, if you were to count up all of
the carbon, hydrogen, and oxygen atoms on each side of the chemical equation, you’d
see that the numbers are equal. And so, the chemical equation is
balanced. So now, we’re ready to choose our
answer. The correct balanced symbol
equation for photosynthesis is 6CO2 plus 6H2O is converted into C6H12O6 plus
6O2.
