Respiration.
i) O2, & ii) H2O.
Oxygen
CO combines with O2 to create CO2. 2CO +O2 --> 2CO2
Optimum temperature Water Food O2 Energy (light or food ) Space to live .
Mitochondria= respiration-energy+o2 Chloroplasts=photosynthesis-food - energy
O2 is a molecule made up of two oxygen atoms. Oxygen itself is an element, but when it combines with another oxygen atom to form O2, it is considered a molecule.
S8 + 8 O2 → 8 SO2 burning sulfur in the presence of oxygen
potassium oxide is formed. 4K + O2 ---> 2K2O
That process is the photosynthesis.Respiration absorbes O2 and release CO2.
In the process of photosynthesis, plants use carbon dioxide (CO2) to produce glucose (food) and oxygen (O2) is released as a byproduct.
we call it photosynthesis. it will make carbohydrates and o2 gas.
When Hydrogen is burned in air it combines with Oxygen to form water. 2H2 + O2 -> 2H2O