Page 76 - Chemistry eBook

malleable, reacts wi
noble gas nonmetal
d temper lectromag emperatur
nd endoth f heat re
(l) at 10 373 J
2260 J
emical re
d pressur eaction sys
a good h oxygen
(1) arrangement of molecules
(2) intermolecular forces
(3) number of molecules
(4) molecular structure
Sample Regents Questions
23 Which statement describes a chemical reaction at equilibrium? Jan 2013 #22
(1) The products are completely consumed in the reaction.
(2) The reactants are completely consumed in
ture netic
e rmic
the reaction.
uired to Choice #2 (3) The concentrations of the products and
0.°C and reactants are equal.
Explanation: F(i4n)d tTheheelectoronecgeatnivtirtay toifoenacsh oelfemthenet opnroducts and Table S (p. 10). reactants are constant.
Boron: 2
action to
Nitrogen: 3
tem
22 Which atom has the weakest attraction for electrons in a chemical bond?
(1) a boron atom (3) a fluorine atom (2) a calcium atom (4) a nitrogen atom
other in rings and networks?
(1) aluminum (3) hydrogen
Answer
Calcium: 1
24 Whichelementhasatomsthatcanbondtoeach
Fluorine: 4
Which atom has the lowest electronegativity (least attraction to electrons)? Calcium.
(2) carbon (4) oxygen
dt
) )
na e
e
oq O
) )
h ne
at STP is not determined by its
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