Copper has two isotopes. Copper-63, which has an atomic mass of of 62.93 u and copper-65, which has an atomic mass of 64.93 u. In any sample of copper atoms, 69.1% will be copper-63 and 30.9% will be copper-65. Calculate the average atomic mass of naturally occurring copper. {Can someone pleases help me.}

i think it is d. e because the next one is igneous.

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.