Which of the following statements about energy in systems is true? energy can be transferred or transformed inside or outside of a system, but energy cannot be destroyed. the total amount of energy in a system must be equal to the total amount of matter in that system. when energy is transferred or transformed within a system, some matter must be changed into energy so that the total amount of energy remains constant.

Energy can be transferred or transformed inside or outside of a system, but energy cannot be destroyed.

Explanation:

A popular principle in science is known as the principle of conservation of energy. It states that energy cannot be created nor destroyed but can be converted from one form to another.

In a system, energy transformations are possible and does happen though inefficiently according to the laws of thermodynamics but energy can never be destroyed following the laws of thermodynamics.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

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