Which of the following is an example of a physical change? O A. A gas is given off when two substances are mixed.
B. A copper rod is hammered into a thin sheet.
C. A solid forms when two clear liquids are mixed.
O D. A matchstick changes color when it burns.

What best explains whether bromine (br) or neon (ne) is more likely to form a covalent bond? bromine forms covalent bonds because it has seven valence electrons, but neon has eight valence electrons and already fulfills the octet rule. bromine forms covalent bonds because it has many electron shells, but neon has only two electron shells and is tightly bound to its electrons. neon forms covalent bonds because it can share its valence electrons, but bromine has seven valence electrons and can gain only one more electron. neon forms covalent bonds because it has only two electron shells, but bromine has many electron shells and will lose electrons in order to fulfill the octet rule.