Which of the following is a physical change?
-burning
-rusting
-freezing
-oxidation

An atom of sodium-23 (atomic number = 11) has a positive charge of +1. give this information, how many electrons does it have? how many proteins and neutrons does this atom have

How does the presence of oxygen affect the chemical pathways used to extract energy from glucose?

The molecular weight of carbon dioxide, co2, is 44.00 amu, and the molecular weight of nitrous dioxide, no2, is 46.01 amu, so no2 diffuses co2