Neon is the element - Ne the symbol
The type of a bond in which two atoms share their electrons is called the covalent bond. A famous example of this is the bond between two hydrogen atoms.
H2SO4 ---> 2H^+ + SO4^2-
Hence n H+ = 9 mols
Mass of H = nM = (9*1) = 9g
Alternately
mass of H2SO4= nM= 4.5*98= 441
Mass of H= mass h2so4 * molar mass of H/molar mass of h2so4
Mass of H= 441 * 2/98 = 9g
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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The answer would be: C. 160.3 J/mol*K
To solve this question, you need to know the equation for Gibbs free energy formula. Entropy is expressed as delta S. The temperature would be expressed as T. Don't forget that temperature use Kelvin as unit, not Celsius
The formula would be:
G= H- T*S
130.5 kJ/mol= 178.3kJ/mol - (25+273.15K)*S
(298.15K)*S=178.3kJ/mol - 130.5 kJ/mol
S= (47.8kJ/mol)/ 298.15K=
S= 0.1603 kJ/mol*K= 160.3 J/mol*K ------> 1kJ= 1000J
