Atomic number refers to the number of protons within the nuclei of an element's atoms (and therefore the number of electrons) while mass number refers to the number of protons and neutrons within the nucleus.
Answer:
67.91 g of CuCl2; 32.09 g of Cu.
Explanation:
The two masses add to 100.0 g, the initial amount of starting material, demonstrating the law of conservation of matter.
<em>The periodic table helps people understand what a substance's atoms can contain, which also provides information on how it can perform a specific action, or how well it can act as a base and so on. When people understand what something is made of, we can figure out what it can be used for. This makes it easier for workers to construct important structures.</em>
<em>Hope this helps and have a nice day.</em>
<em>-Sayonara</em>