Answer:
7?
Explanation:
Its somewhat hard to comprehend the question, but if the way I read it was right, its 7.
Answer: 3 significant figures
Explanation: because in scientific notation only the before and after decimal number are considered but in standard form all numbers including exponents are all significant figures
<span>This is false. A carbohydrate is a carbon-based molecule that can be utilized by living organisms in order to produce energy. A calorie is a unit of energy often used to measure the amount of energy within food. Another example of energy unit is the Joule, more commonly used within physics.</span>
Answer:
<em>What can be added to an atom to cause a nonvalence electron in the atom to temporarily become a valence electron </em>is<u><em> energy</em></u><em>.</em>
Explanation:
The normal state of the atoms, where all the electrons are occupying the lowest possible energy level, is called ground state.
The <em>valence electrons</em> are the electrons that occupy the outermost shell, this is the electrons in the highest main energy level (principal quantum number) of the atom.
So, a <em>nonvalence electron</em> occupies an orbital with less energy than what a valence electron does; in consequence, in order to a nonvalence electron jump from its lower energy level to the higher energy level of a valence electron, the former has to absorb (gain) energy.
This new state is called excited state and is temporary: the electron promoted to the higher energy level will emit the excess energy, in the form of light (photons), to come back to the lower energy level and so the atom return to the ground state.