The correct option is A,
Isotopes are atoms of an element, which have the same number of protons but different number of neutrons in the nucleus of the atom. Thus, isotopes have the same atomic number but different mass number.
Looking at the options given above, you will discover that Chlorine which is given in option A is correct. Both type of chlorine has the same atomic number, which is 17, but they have different atomic masses, the atomic mass of the first one is 35 while that of the second one is 37.<span />
Answer: B
Nitrifying bacterium, plural Nitrifying Bacteria, any of a small group of aerobic bacteria (family Nitrobacteraceae) that use inorganic chemicals as an energy source.
<span>The elements that form the compound don't compare because it doesn't matter about the elements when they are combined. The elements that formed it together is completely different than the outcome compound. </span>
A "3" should but put in front of
<span>"cas o 4 "</span>
