Exam 1 review questions
For the following measured numbers, the number of significant figures is indicated in parentheses. Which is correct?
0.0130 (three)
How many moles (in mol) of Kr are contained in 3.98 × 104 mg of Kr?
0.475 mol Kr
What is the energy in joules of one mole of photon of microwave radiation with a wavelength 0.122 m?
0.980 J
Determine the number of protons, neutrons, and electrons in Se if its mass number is 75.
34 protons, 41 neutrons, 34 electrons
Potassium (K) has an atomic mass of 39.10 amu and only two naturally-occurring isotopes. The K-41 isotope (40.96 amu) has a natural abundance of 6.730%. What is the mass (in amu) of the other isotope?
38.97 amu
V
frequency
Select the arrangement of electromagnetic radiation which starts with the SHORTEST wavelength and increases to LONGEST wavelength.
gamma rays, x-rays, uv rays, infrared rays, microwaves, radio
which is not a SI unit
gram
Gold has a density of 0.01932 kg/cm3. What volume (in cm3) would be occupied by a 33.3 g sample of gold? Correct!
1.72 cm^3
Oxygen is the most abundant element in both Earth's crust and the human body. The atomic masses of its three isotopes, 816𝑂𝑂(99.757%), 817𝑂𝑂(0.038%), 818𝑂𝑂, are 15.9949, 16.9991, and 17.9992 amu, respectively. What is the atomic mass of oxygen.
15.9994 amu
How many of the following units are SI base units? Second Celsius gram meter kilometer
2 (meter and second)
Calculate the wavelength, in nanometers, of the light emitted by a hydrogen atom when its electron falls from the n = 7 to the n = 4 principal energy level.
2.16 × 103 nm
Avagadro's number
6.02 x 10^23
Planck's constant
6.626 x 10^-34
The wavelength of the blue light given off by a mercury vapor street lamp is 436 nm. What is the frequency of this light in s-1?
6.88 × 1014 s-1
How many cubic inches are in 1.00 liter? (1 in = 2.54 cm, 1L = 1000 cm3)
61.0 in^3
An unknown element is composed of onlytwo isotopes, X-79, 78.9183 amuand X-81, 80.9163 amu. If the percentage of X-79 is 50.7%, what is the atomic mass of this element?
79.9 amu
How many orbitals are contained in the third principal level (n = 3) of a given atom?
9
The correct result of the molecular mass calculation for H2SO4 is_______. 4 × 15.9994 + 32.066 + 2 × 1.0079 =
98.079
mixture
A combination of two or more substances that are not chemically combined
chemical energy
A form of potential energy that is stored in chemical bonds between atoms.
homogenous mixture
A mixture in which substances are evenly distributed throughout the mixture
heterogenous mixture
A mixture in which substances are not evenly mixed
substance
A single kind of matter that is pure and has a specific set of properties.
matter
Anything that has mass and takes up space
Isotopes
Atoms of the same element that have different numbers of neutrons
groups/families
Atoms with similarproperties are arranged in vertical columns, known as
halogens
Contains nonmetals, 7 valence electrons in it's outermost energy level. Very reactive
An atom has 28 neutrons and a mass of 52 amu. What element is the atom?
Cr
the atom has: 1.Nucleus(a small core) containing −Protons: positivelycharged particles −Neutrons: neutralparticles 2.Electrons: negativelycharged and low mass particles, outside the nucleus
Earnest Rutherford's Nuclear Theory
metals
Elements that are good conductors of electric current and heat.
Nonmetals
Elements that are poor conductors of heat and electric current
Metalloids
Elements that have properties of both metals and nonmetals.
kinetic or potential
Energy is classified as either
chalcogens
Group 6A
periods
Horizontal rows on the periodic table
Which of the following statements about subatomic particles is/are TRUE? (I) Electrons make up most of the mass of an atom. (II) Neutrons and protons are found in the nucleus of an atom. (III) Protons and neutrons have charges that are opposite in sign but equal in magnitude.
II only
Which of the following statements are TRUE? I. Electrons make up most of the mass of an atom. II. Neutrons and protons are found in the nucleus of an atom. III. Protons and neutrons have charges that are opposite in sign but equal in magnitude.
II only
Which of the following statements about isotopes is/are TRUE? (I) Isotopes of the same element differ only in the number of electrons they contain. (II) Isotopes of the same element have the same mass. (III) Isotopes of the same element have the same number of protons but a different number of neutrons.
III only
h
Planck's constant
Which of these elements exhibits chemical behavior similar to that of oxygen (O)?
S
Jules
SI unit of energy
chemistry
The study of the properties of matter and how matter changes
thermal energy
The total energy of motion in the particles of a substance
groups
Vertical columns on the periodic table
wave
a disturbance that transfers energy from one place to another
SI units
a system of physical units ( SI Units ) based on the meter, kilogram, second, ampere, kelvin, candela, and mole, together with a set of prefixes to indicate multiplication or division by a power of ten.
l
angular momentum quantum number
alkali metals
any metal in Group 1A of the periodic table
average mass of isotopes
atomic mass
A modern periodic table arranges the elements in increasing
atomic number
ml
magnetic quantum number
Ephoton
hv or hc/λ
Atom
is the smallest quantity of matter that still retains properties of matter
density
mass/volume
Which of the following is a correct set of quantum numbers for an electron in a 4d orbital?
n = 4, l = 2, ml = ‒1
noble gasses
non-metals, group 18, the most non-reactive elements
Atomic number (Z) =
number of protons
electrostatic energy
potential energy that results from the interaction of charged particles
n
principal quantum number
C
speed of light
frequency formula
speed of light/wavelength
ms
spin quantum number
potential energy
stored energy that results from the position or shape of an object
The shape of an atomic orbital is associated with_________.
the angular momentum quantum number (l)
alkaline earth metals
the elements in Group 2A of the periodic table
E
the energy of a photon
molar mass
the mass in grams of one mole of a substance
atomic mass
the molar mass of an element is equal to its atomic mass
Atoms are neutral so...
the number of protons must equal the number of electrons
3.00x10^8 m/s
the speed of light in m/s
Mass number
the sum of the number of neutrons and protons in an atomic nucleus
Λ
wavelength
de Broglie wavelength
λ=h/mv
