Answer:
a group of electrochemical cells that can be recharged
Answer: D.
Explanation: A chemical reaction is said to be in a state of equilibrium when the rate of the forward reaction equals the rate of the backward reaction, thus, there is no net change in the concentration of reactants and products.
This problem is honestly, very easy. Just grab a periodic table and find the element in Group 1 and Period 7. But first, let's discuss how the elements are arranged systematically in a periodic table. There are a lot of scientists who contributed to it, but the most famous one is Dimitri Mendeleev. He arranged the elements according to their atomic number. The elements starts from 1 which is Hydrogen up to the heaviest known elements which is Oganesson with an atomic number of 118. As you can observe, there is a gap between groups 3 and 4. This is done so that the periodic table does not take too much space horizontally. Thus, they are just placed at the bottom. These elements are called lanthanides (upper row) and actinides (lower row). The rows in the periodic table are called groups, and the columns are called periods.
Now, the element at the lower left corner (Group 1, Period 7) is Francium, abbreviated as Fr. It has an atomic number of 87. Some elements are actually synthesized, but Francium is a naturally occurring radioactive element. It was discovered by Marguerite Perey in France.
Answer:
I believe you would need to know how much melanon you have and how much melanon your partner has. Correct me if i'm wrong. I hope this helps!
Answer:
Valence electrons are the electrons in the highest occupied principal energy level of an atom.