Many things could indicate that a chemical change has occurred. The release of a gas, or bubbling, etc. Just be careful not to mix it up with physical changes. A chemical change means that the chemical structure is different. You can reverse a physical change, but you cannot reverse a chemical reaction.
<span>Electrons in a nitrogen-phosphorus covalent bond are not shared equally because nitrogen and phosphorus do not have the same electronegativity. The atoms spend more time around the most electronegative atom nitrogen.</span>
