I NEED HELP Which of the following statements is true?

The number of electron shells in an atom is called the atomic number.
Boiling and melting points are chemical properties.
A molecule of oxygen can have atoms of carbon in it.
Elements are substances made of only one type of atom.

What problem would a person have if the nucleic acid in one of his or her cells were damaged?

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.

What type of energy do chemical bonds have? what type of energy is it converted to during chemical reactions? question 15 options: chemical bonds have kinetic energy, which is converted to potential energy during chemical reactions. chemical bonds have electric energy, which is converted to potential energy during chemical reactions. chemical bonds have heat energy, which is converted to kinetic energy during chemical reactions. chemical bonds have potential energy, which is converted to heat energy during chemical reactions.