3. The isotopes of magnesium (and their percent abundance) are Mg-24 (79.0%), Mg-25 (10%), and Mg-26 (11.0%). Calculate the atomic mass of magnesium. NOTE: To one decimal place, the mass of each isotope is equal to the mass number. Thus, the mass of an atom of Mg-24 is 24.0 amu.

yea hi

explanation:

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

the answer is 75.0%.