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:
<em>H.vap = 6.544 kJ/mol</em>
Explanation:
Clausius-Clapeyron Equation
<em>In P = H.vap / RT</em> where T = 20 + 273 = 293K
H.vap = In P (RT) = In 11 (8.314 x 293) = 6543.861 J/mol = 6.544 kJ/mol
Answer:
he main ingredient in most plastic material is a derivative from crude oil and natural gas. There are many different types of plastics – clear, cloudy, solid colour, flexible, rigid, soft, etc. Plastic products are often a polymer resin which is then then mixed with a blend of additives (See polymer vs. plastic).
~+lil more info +~
Plastics are made from natural materials such as cellulose, coal, natural gas, salt and crude oil through a polymerisation or polycondensation process. Plastics are derived from natural, organic materials such as cellulose, coal, natural gas, salt and, of course, crude oil.
6.7639104*10^0 is the answer.
