Answer:
Isotopes are basically atoms of an element that have an unequal number of neutrons and protons. Of course the proton number remains the same, but the neutron number either decreases or increases, which leads to an overall change in mass. However, no chemical properties of the atom/element are changed as the electrons are the same number and do not react. In regards to Helium 4, the original number of neutrons in Helium is 2, and protons 2 as well. We see an equal number of neutrons and protons, hence an unchanged mass, and the element is <em>not</em> an isotope.
Hydrogen atom and chlorine atom makes hydrogen chloride molecules.
It is the lowest point in the substance and possesses chemical elements. Atoms don't exist on their own; instead, they combine to create ions and molecules, which combine to create the substances that we can see, feel, and touch.
One or more atoms joined together by covalent (chemical) connections make up molecules. Atoms can be imagined as circles with a central nucleus (consisting of protons and neutrons) and one or more concentric circles surrounding it that represent the "shells" or "levels" in which the electrons surrounding the atom's nucleus are located as well as markings that distinguish the electron. every level
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Three elements that are likely to have similar chemical and physical properties are
Full moon I’m pretty sure... good luck!