Chemistry exam 2 - practice exam
Complete the following nuclear equation: (206/81)Tl->(206/82)Pb+?
(0/-1)e
Complete the following nuclear equation: (210/84)Po->?+(4/2)He
(206/82)Pb
Complete the following nuclear equation: ?->(218/85)At+(0/-1)e
(218/84)Po
Which of the following nuclear equations correctly describes alpha emission?
(238/92)U->(234/90)Th+(4/2)He
Which of the following is a major advantage of nuclear-fission-based power plants?
-The amount of energy per kilogram of fuel is greater than any other fuel source & -The reactors can be used to produce their own fuel
How many electrons are used to draw the electron-dot structure for acetylene, a covalent compound with the formula, C2H2?
10
The half-life of carbon-14 is 5,730 years. A sample is found to have 1/8 the original amount of carbon-14 in it. How old is the sample?
17,200 years
The number of nonbonding pairs in the water molecule is________
2
Which of the following is the correct electron dot structure for carbon(atomic #=6)?
4 half-full spots
If you mix a typical iodine ion (I, atomic #=53) with a typical barium ion (Ba, atomic #=56), what compound is formed?
BaI2
Which of the following atons has the smallest atomic radius? I, Br, At, F, Cl
F
Which element has the atomic # 12? Na, Mg, C, Be, B?
Mg
Which of the following elements will most likely form an ion with a +2 charge? Na, Si, Ne, Mg, Cl
Mg
List the following bonds in order of increasing polarity
N-N < N-O < N-F < H-F
Which of the following experiments helped to determine the charge of an electron and (indirectly) its mass?
R. Millikan's oil drop experiments
What is a molecule?
a group of atoms that are held together by covalent bonds
What does the following element description actually mean? "hydrogen-2"
a hydrogen with 1 neutron and 1 proton
If 3 samples have the half-lives listed below, which is the most radioactive? "hours, million years, minutes, years"
a sample with a half-life of 20 minutes
What is the name for the following polyatomic ion? CH3CO2-
acetate
The following statement describes which subatomic particle best? "It is located outside of the nucleus"
an electron
When (226/88)Ra decays by emitting an alpha particle, what is the atomic # and atomic mass of the resulting nucleus?
atomic # = 86; atomic mass = 222
What is the molecular shape of the following molecule (o---š===o)
bent
Rank the following by relative amounts of energy, from most energetic to least
gamma rays, blue light, red light, radio waves
Which of the following statements does not describe a proton?
it orbits around the nucleus of an atom
The cathode ray consists of________
negatively charged particles
Which of the following beams is due to an energetic non-visible light wave? a)positive, b)neutral, c)negative
neutral
Isotopes of the same element have a different number of________
neutrons
What is the main technical difficulty in dealing with fusion reactions?
the amount of energy needed to overcome the electrical repulsion of the reactants is extremely high
Which of the following statements best describes the strong nuclear force?
the force is very strong but has a very short range
The acronym VSEPR stands for_______
valence shell electron pair repulsion
Why can't we see atoms?
we see with light energy and the wavelength of light is larger than the atom and is not reflected
Which of the following has the longest wavelength? "shortest space between each top of wave or widest space between each top of wave?"
widest space
How many covalent bonds would the following generic atom usually form?(all spots full)
would usually not form any covalent bonds