Answer:
The period 4 alkaline-earth metal has the name Calcium. An isotope of this element having 20 neutrons has a mass number of 40.
Explanation:
Looking at the periodic table 4th row for the alkaline-earth metal, we can find Calcium which has an atomic number of 20 (or protons number, or z). The mass number is given by the sum of protons and neutrons. If the number of protons in this case is 20 and the number of neutrons is also 20, the mass number A = 40.
Heat energy is needed for evaporation to happen.
Just breaking stuff so yea that’s it
Answer:
<em>A process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in</em> <u><em>physical form or a nuclear reaction.</em></u>
Explanation:
A process that involves rearrangement of the molecular or ionic structure of a substance, as opposed to a change in <u><em>physical form or a nuclear reaction.</em></u>
Answer:
Magnesium reacts with dilute hydrochloric acid in a conical flask which is connected to an inverted measuring cylinder in a trough of water. The volume of hydrogen gas produced is measured over a few minutes, and the results are used to plot a graph........