Determine the total number of electrons present in the atom, molecule or ion below: N2
10
9
12
14
A gamma ray of wavelength 1.00 X 10^-8 cm has enough energy to remove an electron from a hydrogen atom
How many protons are in a 127 I- ion?
55
54
50
53
Determine the total number of electrons present in the atom, molecule or ion below: BH3
Which of the following pairs can be used to illustrate the law of multiple proportions?
NO and NO2
H20 and HCl
NH4 and NH4Cl
ZnO2 and ZnCi2
CH4 and CO2
After an anion has lost an electron it becomes a/an and has a charge.
Anion, Positive
Isotope, Positive
Anion, Negative
Cation, Positive
Compound, Positive
Which one of the following substance is not a chemical compound?
Co
HF
H2S
NO
When strontium salt is ignited it burns with a red flame. The frequency of the light given of by this flame is greater than
Gamma rays
x-rays
yellow light
ultraviolet light
infrared light
How many electrons are present in Be2+ ion?
4
6
2
7
A pure substance composed of two or more different elements is a(n)?
An atom containing 34 Protons 43 Neutrons and 34 electrons would have the symbol?
77Se
77Ir
77Tc
43Se
43Te
The scientist who discovered the law of conservation of mass and is called the father of modern chemistry is?
Lavoisier
Boule
Rutherford
Avagadro
Which of the following is incorrect?
the lowest possible energy state of a molecule or atom is called it's ground state
diffraction produces both constructive and destructive interference
the emission spectrum of hydrogen contains a continuum of colors
Niels Bohr developed a quantum model for the hydrogen atom
All matter displays both particle and wavelike characteristics
Mendeleev is given the most credit for the concept of periodic table elements because:
he grouped elements into traids of similar properties
he emphasized it's usefulness in predicting the existence and properties in unknown elements
Wherever it is found water always contains oxygen and hydrogen in the mass ration 8 to 1. taken by itself this fact demonstrates what natural law?
conservation of mass
definite composition
multiple proportions
the atomic theory
periodicity
Rutherford bombarded gold foil with alpha (a) particles and found that a small percentage of the particles were deflected. Which of the following was not accounted for by the model he proposed for the structure of atoms?
the small size of the nucleus
the charge on the nucleus
the total mass of an atom
the existence of protons
the presence of electrons outside the nucleus
which of these isotopes have the greatest number of neutrons?
38 Cl
40 Ar
40 K
40 Ca
38 Sc
which of the following is an example of quantitative observation?
the piece of metal is longer than a piece of wood
solution 1 is much darker than solution 2
the liquid in beaker A is blue
the temp. of liquid is 60 degrees C
at least two of the above observations
Fe has that is unpaired in it's d orbitals
one electron
two electrons
three electrons
four electrons
Infrared radiation from the sun has a wavelength of 6200nm. Calculate the energy of one photon of that radiation
4.1 x 10 -39 J
4.1 x 10 -30 J
3.2 x 10 -29 J
3.2 x 10 -26 J
between 10-20 and 10-19 J
How many protons and electrons are present in Br- ion?
An atom of the isotope chlorine-39 consists of the photons, neutrons and electrons?
Which mass law is demonstrated here?
Law of conservation of mass
law of definite composition
law of conservation of mass and law of definite compositions
law of conservation of mass and law of multiple proportions
The chemist credited for inventing a set of symbols for writing elements and system for writing the formulas of compounds (and for discovering selenium, silicon, and thorium) is:
Bohr
Berzelius
Planck
Maldeeve
A is a pure substance that is composed of only one type of atom.
What is the correct symbol for Potassium?
[Ne]3s^2 3p^5
The first scientist to show that atoms emit any negative particles was?
J.J Thompson
William Thompson
John Dalton
Ernest Rutherford
Rutherford's experiment with alpha particles scattering by gold foil established that?
Electrons are negative
Electrons bounce
Protons are not evenly distributed
The scientist who discovered the law of conservation of mass and is also called the modern father of chemistry?
What is the name of the element with the symbol Cr?
Consider the following two compounds: H20 and H2O2, according the the law of multiple proportions the ration of hydrogen atoms per gram of oxygen in H2O to hydrogen atoms per gram of oxygen in H2O2 is
2;2
3;2
1;2
2;1
What is the I quantum number for 4f orbitals?
How many electrons in an atom can have the quantum numbers n=3, I=2?
Which subatomic particle was discovered using cathode ray?
Bluetooth headsets use microwave radiation with a wave length of 12.32cm, what is the frequency of the light given of the electromagnetic radiations (s-1) Enter is expo format.
discovered the nucleus
measured the charge of electron
discovered x-rays
measured the charge/mass ratio of an electron
invented the cathode ray tube
What is the number of Neutrons and electrons in the ion 209Bi2+
Who is credited with discovering the atomic nucleus?
Which inventor is mismatched?
Lavoisier; law of conservation of mass
Proust; mass of an electron
Dalton; atomic theory
Mendeleev; periodic table
Arrhenius; acids produce H+ in water
Determine the total number of electrons present in the atom; NH4+
Which mass is demonstrated by the observation that a sample of potassium chloride from Chile contains the same percent by mass of potassium as one from Poland?
Which of the following is classified as an element?
I2
KCl
C6H12O6
CO
Which of the following statements refers to the Heisenberg uncertainty principles?
It is impossible to accurately know both the exact location and momentum of a particle
The exact position of an electron is uncertain
A hypothesis is a
mathematical formula that models a pattern of behavior
concise statement of a behavior that is always the same under the same conditions
set of experiments designed to test a theory
well tested, unifying principle that explains facts
tentative explanation or predictions based upon experimental observations
The number of nucleons (Protons and Neutrons) in a 236U2+ nucleus?
All of the following are true except?
the n=3 shell has no f subshell
there are three p orbitals in every shell of an atom then n=1 shell
all s orbitals have a spherical shape
each d subshell has five d orbitals
the energiesof subshell in the shells (energy levels) of a hydrogen atom vary as s<p<d etc.
According to the Aufbau principle which sublevel is filled after the 5s sublevel?
5p
4f
3d
4d
5d
What is the atomic mass for the halogen that lies in period 5?
131.3 amu
127.6 amu
approx. 210
53 amu
Which of the following sets of elements have the [noble gas] ns^2 np^2
O, S, Se, Te, Po
N, P, As, Sb, Bi
Cl, Br, I, At
C, Si, Ge, Sn, Pb
Tl, Zr, hf
How many unpaired electrons are there in the ground state of a manganese atom?
1
5
0
How many unpaired electrons are there in a manganese atom?
Rank the following atoms in order of the largest to the smallest atomic radius: Al, P, Cl, K
K>Al>P>Cl
Al>K>P>Cl
P>Al>K>Cl
K>P>Al>Cl
Larger first ionization energy, Li or Be?
Which of the following process represents the ionization energy of bromine?
Br(I) -> Br+ (g) + e-
Br(g) -> Br+ (g) + e-
Br(S) -> Br+ (S) + e-
Br(S) -> Br+ (g) + e-
Br2(g) -> Br2+ (g) + e-
How many electrons can be contained in the orbitals of a subshell with I=3?
In a given period this group has the element with the largest atomic radius.
Group 3A
Group 4A
Group 2A
Group 1A
Group 5A
What set of the elements below includes just the nonmetals? GA, P, Ra, Li, La, Xe
P, I, Xe
P, I, La
I, Xe, Ra
Ga, P, Xe
P, I, Li
Which of these subshells is incorrect?
5s
2p
3f
Which of the following subshells in a typical polyelectronic atom fills last?
1s
4s
More info. is needed =
In a modern periodic table, the order in which the elements are placed is based on
atomic mass
mass number
atomic series
atomic number
atomic size
chemical reactivity
Which of the following atoms is a non-metal?
Fr
Ge
N
Hg
None of these are non-metals
Hydrogen and lithium react very differently, although they are both members of Group 1. What is the primary reason for this difference?
Electron affinity increases going down a group
The metallic character increases going down a group
The ionization energy increases going down
There is a very large difference in the atomic radii of H and Li
Electronegativity increases going down a group
With increasing value of the quantum number l, subshells are named s, p, d, f, g, h, i, etc.
How many l=4 orbitals are allowed in a l=4 subshell?
Enter your answer as a whole number without units.
Consider the following orderings.
I. Na + < Mg 2+ < Al 3+ < Si 4+ II. Be < Mg < Ca < Sr III. I < Br < Cl < F IV. Al < Si < P < Cl Which of these give(s) a correct trend in ionization energy?
1, 3,4
none of them
2, 4
1, 4
3
Ionization energy increases with an increasing number of electrons
An atom of which of the following elements has the smallest atomic radius?
At
F
I
Br
Cl
Determine the number of unpaired electrons in ground state atoms of P and Cl, respectively.
5, 3
5, 1
3,1
3,2
3, 5
What is the number of unpaired electrons in sulfur atom?
Give the ground-state electron configuration, symbol, and group number from each partial (valence-level) orbital diagram.
[Xe] 5s24d3; Ta; 5B (5)
[Kr] 5s24d3; Nb; 5B (5)
[Ar] 5s24d3; V; 5B (5)
[Kr] 5s24d3; Tc; 7B (7)
none of these
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