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The set of compounds that have the same empirical formula is b) N₂O₄ and NO₂.
The Empirical Formula is the most simple representation of the atom ratio in a chemical compound. Of the listed sets of compounds, the only in which the atom ratio is the same for both compounds is the pair N₂O₄ and NO₂ in which the atom ratio N:O is 1:2. The Empirical Formula for this pair is NO₂.
N₂O₄ has the same atom ratio as NO₂ but this formula has each atom multiplied by two. However, its Empirical Formula is the same.
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Zn + H₂SO₄ = ZnSO₄ + H₂
answer (3) <span>single replacement
hope this helps!</span>
Answer:
B, C
Explanation:
The atoms or ions with the valid Lewis dot structures are B and C.
In A;
The Lewis structure of the carbon is correct. Each of the four dots represent the four valence electrons.
The nitrogen with one dot on top, left and to the bottom and has a charge of minus 3 is wrong. For it to have a charge of -3 it must have 8 lewis dots ( two on the top, right, bottom and to the left)
The nitrogen with four dots (on top, right, bottom and to the left) is wrong.
In B;
An oxygen has two dots on top and bottom and one dot to the left and to the right. This is correct , the 6 dots represent the valence electrons of oxygen.
In C;
A carbon has two dots on top, right, bottom and to the left and a charge of plus four. This is correct because the charge indicates that it has gained four extra electrons so its valence electrons is now 8.
In D;
An oxygen has two dots on top, left and to the bottom and a charge of minus 2. This is wrong because the lewis dots are incomplete. Two dots are missing.
The moles of the gas in the sample is 0.391 moles
calculation
by use of ideal gas equation, that is Pv=nRT
where n is number of moles
P(pressure)= 660 mmhg
R(gas constant) = 62.364 l.mmhg/mol.K
T(temperature)= 25 +273 = 298 k
by making n the subject of the formula
n= Pv/ RT
n is therefore= (660mm hg x11 L)/( 62.364 L.mmhg/mol.k x298 K) = 0.391 moles
