Answer:
A.
Explanation:
if it's the same element the protons will always be the same, but have different neutrons, and neutrons is made up of protons and atomic mass, which atomic mass numbers can be calculated different where in return gives different numbers of neutrons.
EX: say the element is carbon, carbon has 6 protons and that won't change, but carbon can have an atomic mass of 12, 13, or 14, etc. so when you make up the neutrons you add protons and atomic mass, 6 + 12 = 18 N
6 + 13 = 19 N
6 + 14 = 20 N
The correct answer is:
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" F and Br , because they are in the same group" .
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Note:
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Choice [B]: "F and Br ; because they are in the same period" ; is incorrect; since "F" and "Br" are not in the same "period" (that is, "row").
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Choice [C]: "Na and Mg; because they are in the same group {"column"} ; is incorrect; since: "Na" and "Mg are NOT in the same group {"column"].
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Choice [D]: "Na and Mg" ; because they are in the same period {"row"}; is incorrect. Note: "Na" and "Mg" are, in fact, in the same period {"row"}. However, as aforementioned, {Mg and Na} are not in the same group {"column".}.
Note: The similiarities in physical and chemistry properties among elements are determined and organized — or tend to be so—by "groups" {"columns"} — NOT by "periods" {rows}.
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Answer: I think that is 55
Explanation: I hope I help
Answer:
a
Explanation:
it is an electrolyte because of its strong polar chemical bond
Explanation:
Oxygen - 65.0%
Carbon - 18.5%
Hydrogen - 9.5%
Nitrogen - 3.2%
Calcium - 1.5%
Phosphorus - 1.0%
Potassium - 0.4%
Sulfur - 0.3%
Sodium - 0.2%
Chlorine - 0.2%
Magnesium - 0.2%
Others < 1.0%
The above is the elements present in the human body. They compose of almost all the 20 first elements on the periodic table. The first 20 elements are seen on all sides of the periodic table.
