Answer:
Atoms are composed of extremely small particles that are too small to be seen with an optical microscope.
Size at the atomic level is measured on the nanoscale.
Atoms are made of three subatomic particles - protons, neutrons, and electrons.
Protons:
- positively charge
- located in the nucleus
Neutrons:
- no charge (neutraly charge)
- located in the nucleus
Electrons:
- negatively charged
- located around the nucleus
Atomic number (Z) = the number of protons in the nucleus of an atom.
(i apologize, i don't understand the last part...)
Answer:
Y and group number 17
Explanation:
Iodine is the chemical element of symbol I and atomic number 53, belonging to group 17 or of the halogens, in the periodic table. It is an element that we can find both in its molecular form, and in a diatomic way. In addition, iodine is a trace element and is used in the field of medicine and photography, as well as in some cases it is used as a dye. In the field of chemistry, iodine is the least reactive halogen element. Like the rest of the halogens, iodine also forms diatomic molecules, in this case the diiodine (I2).
Iodine is part of numerous compounds, despite being the element with the lowest reactivity in its group. It has some characteristics of metals, and their oxidation states are -1, + 1, + 3, + 5, + 7.
Despite its use, it is the halogen as a minor abundance, with only 0.14 ppm concentration in the earth's crust, however, in seawater its abundance is exactly 0.052 ppm.
Answer/Explanation:
62.559%
mass of an element X 100%
mass of the compound
Scientific Notation: 3.45 x 10^5
E Notation: 3.45e5
Planets revolve around the sun because of gravity. When the planets were made, the sun's gravity was strong enough so that the planets continued to stay around the sun and orbit.
