Question

What's the balanced equation for cellular respiration?

Answer 1

Correct answer is:

$C_{6}H_{12}O_6+6O_{2}\Rightarrow 6CO_{2}+6H_{2}O+energy$

But how to get there?

Let's start with simple explanation of what exactly is cellular respiration. 

Cellular respiration is a multistage biochemical oxidation process of organic substances when prime product is energy (ATP - adenosine triphosphate) and other are released waste products. Cellular respiration takes place even if other metabolic processes are stopped, but cellular respiration may differ in particular organism groups.Some reactions during whole process of cellular respiration are similar in all types of living organisms.

Cellular respiration is prime indication of declining living processes.Only viruses which are on the edge of living organism and chemical particle are not performing cellular respiration.But to the point :P

In cellular respiration all substrates which are in the cell might be organic, but mostly we are using sugar oxidation - glucose in the presence of oxygen. Chemical formula of sugar looks like this:

$C_{6}H_{12}O_6$

Oxygen is just

$O_2$

so for now we have just part of the equation:

$C_{6}H_{12}O_6+O_{2}\Rightarrow$

But what would be on the right hand side?

It's quite simple, remember equation of full combustion? If we want to burn something we need oxygen like in the equation, so the product of this equation would be carbon dioxide, water and of course energy (ATP).Carbon dioxide formula looks like this:

$CO_{2}$

As a reminder water formula:

$H_{2}O$

Full formula would look like that:

$C_{6}H_{12}O_6+O_{2}\Rightarrow\ CO_{2}+H_{2}O+energy$

But still as you see this equation is unbalanced, after balancing it would like that:

$C_{6}H_{12}O_6+6O_{2}\Rightarrow 6CO_{2}+6H_{2}O+energy$

At the end I would like to explain one more thing. Energy which has been released during this process is part of high-energy connection which might be used to perform chemical reactions in the cell or to move organism for example in muscles. We need to remember that production of ATP is not happening with 100% efficiency and part of this energy is released as heat.