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.
Index fossils<span> can be </span>used<span> to help determine the relative age of </span>rock<span> layers. </span>Index fossils<span> are from species that only existed for a short time. </span>Index fossils<span> are found in</span>rock<span> layers. Trilobites and Graptolites are </span><span>index fossils.</span>
Answer:
You need two potassium atom to form an ionic bond with one sulfur atom. Pottassium ions are formed by donating losing their electrons in the outermost shell, thr lost electrons are gained by sulphur atom to form 2K+ and S2-, respectively. The attraction between the positive ions and negative ions gives rise to the ionic bond and the molecular formula is K2S
Explanation:
Answer:
H2O2
Explanation:
2 hydrogen, 2 oxygen wikipedia it
Answer:
4.25*10^18
Explanation:
1 mole =6.023*10^23 particles
so 7.07*10^-6 mole=6.023*10^23*7.07*10^-6 particles=4.25*10^18 particles
