What is the mass percent of hydrogen in water?
a: 5.60
b: 11.2
c: 33.3
d: 88.8 - correct answer -b
How many atoms are in 5.80 moles of He?
a: 3.49 × 10^24
b: 6.02 × 10^23
c: 1.03 × 10^23
d: 4.00 - correct answer -a
What is the value of n when the empirical formula is C3H5 and the molecular mass is 205.4 g/mol?
a: 10
b: 0.02
c: 140
d: 5 - correct answer -d
How many atoms are in 15.6 grams of silicon?
a: 0.555
b: 3.34 × 10^23
,Chemistry 101 Final Exam
c: 2.64 × 10^26
d: 438 - correct answer -b
What is the correct value for Avogadro's number?
a: 6.022 × 10^2.3
b: 6.022 × 10^33
c: 6.022 × 10^23
d: 6.023 × 10^22 - correct answer -c
The empirical formula for C6H6 is C3H3.
True
False - correct answer -False
Water is 11.2% hydrogen by mass.
True
False - correct answer -True
One mole of CO2 gas contains 1 mole of carbon atoms and 2 moles of oxygen atoms.
True
False - correct answer -True
Avogadro's Number is 6.022 × 1023.
True
, Chemistry 101 Final Exam
False - correct answer -True
A 500. gram iron ore sample was determined to contain 242 grams of iron. What is the mass percent of
iron in the ore?
a: 32.6
b: 48.4
c: 51.6
d: 93.7 - correct answer -b
What is the mass of 0.560 moles of chlorine gas?
a: 19.9
b: 39.7
c: 127
d: 63.3 - correct answer -b
How many molecules of nitrogen monoxide are in a 22.5 gram sample?
a: 4.51 × 10^23
b: 7.33 × 10^23
c: 4.06 × 10^23
d: 5.86 × 10^23 - correct answer -a
How many molecules of sulfur trioxide are in 78.0 grams?
a: 5.87 × 10^23
b: 7.33 × 10^23
c: 0.974