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Question
An element consists of three isotopes. The abundance of one isotope is 92.21% and its atomic mass is 27.97693 u. The abundance of the second isotope is 4.70% and its atomic mass is 28.97649 u. The atomic mass of the third isotope is 29.97376 u. What is the average atomic mass of the element?A.28.09 u
B.28.98 u
C.28.96 u
D.29.87 u
E.29.07 u
Answer
This answer is hidden. It contains 2 characters.
Related questions
Q:
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H2O2(aq) H2O() + 1/2 O2(g)
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Q:
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Q:
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Q:
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Q:
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Q:
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Q:
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Q:
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Q:
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A.
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D.
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If a metal crystallizes in a primitive cubic lattice, each metal atom has ____ "nearest neighbors."
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Q:
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C.primitive cubic < face-centered cubic < body-centered cubic
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Q:
Which equation represents the number of atoms in a body-centered cubic unit cell?
A.
B.
C.
D.
E.
Q:
The solubility product equilibrium constant, Ksp, of silver bromide is 5.4 10-13 at 298 K.
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Q:
What is the equilibrium constant for reaction below at 25 C? (R = 8.314 J/Kmol)2 NO(g) + O2(g) 2 NO2(g)given DfG [NO(g)] = +86.6 kJ/mol and DfG [NO2(g)] = +51.2 kJ/mol.A.3.9 10-13B.1.0C.2.6 1012D.1.6 106E.3.8 1028
Q:
All of the following relationships are true EXCEPT
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B..
C..
D..
E..
Q:
Calculate DrG for the combustion of benzene at 325 K.2 C6H6() + 15 O2(g) 12 CO2(g) + 6 H2O()Species DfH (kJ/mol) S (J/Kmol)C6H6() 49.0 173.3O2(g) 0 205.1CO2(g) -393.5 213.7H2O() -285.8 67.0A.-6386 kJ/mol-rxnB.-6078 kJ/mol-rxnC.-7251 kJ/mol-rxnD.-8611 kJ/mol-rxnE.+1431 kJ/mol-rxn
Q:
If a chemical reaction is exothermic, but not spontaneous, which of the following must be true?
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B.DrG < 0, DrS > 0 and DrH > 0
C.DrG > 0, DrS < 0 and DrH > 0
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