Mixing baking soda with vinegar to form CO2
(Isn't the one used to make volcano models)
The correct option is C.
An atom can be either in the ground state or in an excited state. An atom is said to be in the ground state, if the total energy of its electron can not be lowered by moving one or more electrons into different orbitals. At the ground state, the electrons in the atom have the lowest energy possible and they are stable. On the other hand, an atom is said to be in an excited state, if the energy of its electrons can be lowered by transferring one or more electrons into different orbitals. An atom in an excited state has more energy and is less stable.
Answer:19. He says that he’s been really tired since several weeks ago. 20. A friend of us is going to pick us up at the airport. 21. I’ve worked like a waiter in the past, but I wouldn’t want to do it again. 22
Explanation:
