The statement that best describes the difference between ionic and covalent bonds is: A. Ionic bonds share electrons and covalent give and take electrons
B. Covalent bonds share electrons and ionic give and take electrons
C. Ionic bonds form compounds that have a charge and covalent bonds do not
D. There are no differences between the bond types

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

the maximum mass of nh3 is nh3 in grams