CHEM 120 MIDTERM PARTICIPATION Qs 1-17
The change in enthalpy (delta-H) can be calculated as: Δ H = n C p Δ T
This is correct whether the reaction is conducted at constant volume or constant pressure or neither.
true
Antoine Lavoisier discovered which element?
O
Which of the following hypotheses is NOT part of John Dalton's "Atomic Theory"?
Mass is neither created nor destroyed
What is the key feature of JJ Thomson's "plum pudding" model of the atom?
The positive charge is concentrated in a nucleus
In Rutherford's gold foil experiment, what result surprised him?
A few alpha particles bounced back from the foil
Isotopes have:
the same number of protons but different numbers of neutrons
The isotope Carbon-14 has how many neutrons? (The Z-value for C is 6)
8
,Deuterium is heavier than Tritium.
False
Which of the following is an example of "allotropes"?
Red and white forms of elemental phosphorus
Which of the following is not an area of the periodic table?
Conductors
Which of the following elements is not naturally abundant?
Curium (Z=96)
In the Mass Spectrometry experiment:
lighter ions deflect more easily than heavier ions when a magnetic field is applied.
If an element X is mono-isotopic (i.e., has only one isotope), how many lines will be present in the mass
spectrum of X2?
1
Why is the atomic mass of the element chlorine (Cl) on the periodic table listed as 35.45 amu and not as
a whole #? Cl has two isotopes.
, It is the weighted average of the atomic masses of the naturally abundant isotopes.
Given that the atomic mass of H is approximately 1 amu and O is approximately 16 amu, the molar mass
(molecular weight) of H2O2 is approximately:
34
Combustion analysis, also known as "Elemental Analysis" provides the %C, %H and %N in a sample, and
with this information chemists can determine the molecular formula of the unknown sample containing
C, H and N atoms.
false
The empirical formula of C16H20O8N2 is:
C8H10O4N
The following equation shows a balanced combustion reaction:
CH4 + 2 O2 -----> CO2 + 2 H2O
Based on this reaction, if I react 3 moles of CH4 with 5 moles of O2, what is the limiting reagent?
O2
The actual yield of a reaction is usually _____________________ the theoretical yield.
Lower than
Silver chloride (AgCl) is soluble in water.
The change in enthalpy (delta-H) can be calculated as: Δ H = n C p Δ T
This is correct whether the reaction is conducted at constant volume or constant pressure or neither.
true
Antoine Lavoisier discovered which element?
O
Which of the following hypotheses is NOT part of John Dalton's "Atomic Theory"?
Mass is neither created nor destroyed
What is the key feature of JJ Thomson's "plum pudding" model of the atom?
The positive charge is concentrated in a nucleus
In Rutherford's gold foil experiment, what result surprised him?
A few alpha particles bounced back from the foil
Isotopes have:
the same number of protons but different numbers of neutrons
The isotope Carbon-14 has how many neutrons? (The Z-value for C is 6)
8
,Deuterium is heavier than Tritium.
False
Which of the following is an example of "allotropes"?
Red and white forms of elemental phosphorus
Which of the following is not an area of the periodic table?
Conductors
Which of the following elements is not naturally abundant?
Curium (Z=96)
In the Mass Spectrometry experiment:
lighter ions deflect more easily than heavier ions when a magnetic field is applied.
If an element X is mono-isotopic (i.e., has only one isotope), how many lines will be present in the mass
spectrum of X2?
1
Why is the atomic mass of the element chlorine (Cl) on the periodic table listed as 35.45 amu and not as
a whole #? Cl has two isotopes.
, It is the weighted average of the atomic masses of the naturally abundant isotopes.
Given that the atomic mass of H is approximately 1 amu and O is approximately 16 amu, the molar mass
(molecular weight) of H2O2 is approximately:
34
Combustion analysis, also known as "Elemental Analysis" provides the %C, %H and %N in a sample, and
with this information chemists can determine the molecular formula of the unknown sample containing
C, H and N atoms.
false
The empirical formula of C16H20O8N2 is:
C8H10O4N
The following equation shows a balanced combustion reaction:
CH4 + 2 O2 -----> CO2 + 2 H2O
Based on this reaction, if I react 3 moles of CH4 with 5 moles of O2, what is the limiting reagent?
O2
The actual yield of a reaction is usually _____________________ the theoretical yield.
Lower than
Silver chloride (AgCl) is soluble in water.
