SEPTEMBER 2022-QUESTIONS AND 100% CORRECT
VERIFIED ANSWERS| WELL GRADED A+
When comparing the second ionization energies of the atoms across the same row of
the period table, which of the following groups will have the atom with the lowest value?
(Group 1, Group 2, Group 14, Group 16) - CORRECT ANSWERS-Group 2.
What is the mass of water necessary to generate 11.2 L of hydrogen gas if calcium
metal reacts with water at standard temperature and pressure? (2.0 g; 4.5 g; 9.0 g; 18.0
g) - CORRECT ANSWERS-18.0 g.
If elemental hydrogen forms a metallic solid under extreme pressure, as mentioned in
the passage, the chemical properties of the metallic hydrogen formed should be the
most similar to which element? (Germanium; aluminum; magnesium; lithium) -
CORRECT ANSWERS-Li.
The last step in the synthesis of a compound known as 18F-FDG is a hydrolysis
reaction to remove the four acetyl (OAc) protecting groups, If 524 mg of acetylated 18F-
FDG is hydrolyzed, how many millimoles of the acetyl group are removed in the
reaction? (note: the molar mass of the acetylated 18F-FDG is 349.31 mg/mmol). (0.4
mmol; 1.5 mmol; 6.0 mmol ; 7.5 mmol) - CORRECT ANSWERS-6.0 mmol
Compared to the effective nuclear charge of 18^O, the effective nuclear charge of 18^F
is? (higher because 18^F and 18^O have the same number of core electrons, but 18^F
has fewer neutrons; lower because 18^F has more valence electrons than 18^O; higher,
because 18^F and 18^O have the same number of core electrons but 18^F has more
protons; lower, because 18^F has an equal number of protons and electrons). -
CORRECT ANSWERS-Higher because 18F and 18O have the same number of
electrons but 18F has more protons.
If a cyclotron producing protons for a beam is replaced with another cyclotron in which
the kinetic energy of the photons is doubled, what is the ratio of the speed of the
protons produced by the original cyclotron to the speed of the protons produced emitted
by the new cyclotron? - CORRECT ANSWERS-1: square root (2)
As the kinetic energy of a the protons in a beam is increased, what happens to the
average depth in the body that the protons penetrate? (Note: assume the protons move
in a straight line and slow down at a constant rate). (The depth decreases; the depth
increases; the depth remains constant; the depth increases then decreases). -
CORRECT ANSWERS-The depth increases.
Matter falling in the gravitational field of a central mass can form a hot, charged fluid.
The fluid matter orbiting some stars radiates infrared light, but the matter orbiting black
holes emits x-rays. Which of the following explains this discrepancy? The matter orbiting