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WorksheetsChemistry Unit 3 Practice Test
Total questions: 40
Worksheet time: 20mins
A certain compound is composed of elements A and B. It always has the same mass ratio of A to B because
all atoms have the same mass.
A and B have characteristic masses.
A and B have identical masses.
any excess A or B will be destroyed
Carbon dioxide or CO2 will always be a 1 to 2 ratio of carbon to oxygen according to the Law of Definite Proportions.
True
False
If 2 g of element K combine with 10 g of element L, how many grams of element K combine with 20 g of element L?
10 g
4 g
20 g g
5 g
The two oxides of carbon, CO and CO2, are explained by the
periodic law.
law of multiple proportions.
atomic law
law of conservation of mass
If two or more compounds are composed of the same two elements, the ratio of the masses of one element that combine with a fixed mass of the other element is a simple whole number. This is a statement of the law of
conservation of mass.
mass action.
multiple proportions
definite proportions
If 3 g of element C combine with 8 g of element D to form compound CD, how many grams of D are needed to form compound CD3?
8 g
16 g
24 g
19 g
Oxygen can combine with nitrogen to form two compounds, nitrogen monoxide and nitrogen dioxide. The ratio of the masses of oxygen that combine with a given mass of nitrogen is 1:2. This is an example of
the law of conservation of mass.
the law of conservation of energy.
the law of multiple proportions.
Dalton's atomic theory
According to the law of definite proportions, any two samples of H2O have
the same mass.
slightly different molecular structures.
the same melting point
the same ratio of elements
Who was the Russian scientist who studied chemistry and organized the periodic table by atomic mass?
John Dalton
Robert Brown
Jons Berzelius
Dmitri Mendeleev
Who was the English scientist who first recognized that the ratio of the number of atoms that combine is the same as the ratio of the masses that combine?
John Dalton
Jon Newlands
Edward Morley
Jons Berzelius
Who was the scientist who discovered the electron using the cathode ray tube?
Dalton
Chadwick
Thomson
Mendeleev
Who discovered the nucleus by bombarding gold foil with positively charged particles and noting that some particles were widely deflected?
Rutherford
Dalton
Chadwick
Bohr
In Rutherford's experiments, very few positively charged particles
dissolved the metal
were greatly deflected back from the metal.
passed straight through the metal
combined with the metal
Rutherford fired positively charged particles at metal foil and concluded that most of the mass of an atom was
in the electrons
evenly spread throughout the atom
concentrated in the nucleus
in rings around the nucleus
The nucleus of an atom has all of the following characteristics EXCEPT that it
is positively charged.
is very dense.
contains nearly all the atom's mass
contains nearly all the atom's volume
Protons and neutrons strongly attract when they
are moving fast.
are very close together.
are at high energies
have opposite charges
Most of the volume of an atom is occupied by the
nucleus.
electron cloud
nuclides
protons
The most common form of hydrogen has
no neutrons.
one neutron.
two neutrons
three neutrons
The only radioactive form of carbon is
Carbon-14
Carbon-12
Carbon-13
There are no radioactive forms of Carbon
The Hydrogen-2 or deuterium atom consists of
one proton, two neutrons, and two electrons.
one proton, one neutron, and one electron.
one proton, two neutrons, and one electron.
two protons, one neutron, and one electron.
The total number of protons and neutrons in the nucleus of an atom is its
atomic number.
mass number.
number of neutrons.
Avogadro's number.
As the atomic number decreases, the number of electrons in an atom
decrease
increases
remains the same
is undetermined
All atoms of the same element have the same
atomic mass
number of neutrons.
mass number
atomic number
In determining atomic mass units or amu, the standard is 1/12 the mass of a(an)
C-12 atom.
C-14 atom.
H-1 atom
O-16 atom
The abbreviation for atomic mass unit is
amu.
mu.
a.
u.
A single atom of an isotope does not have a(n)
relative atomic mass.
atomic number.
mass number
average atomic mass
The average atomic mass is a weighted average of all the isotopes that an element contains times it percent abundance.
True
False
The mass of 1 mol of Lithium (atomic mass 6.941 amu) is
51.996 g.
6.941 g.
6.022 x 1023 g.
1 g.
A quantity of carbon (atomic mass 12.011 amu) contains 6.02 x 1023 atoms. The mass of the carbon is
6.02 × 1023 g.
12.011 g.
22.99 g.
not determinable
The mass of 3.00 moles of sulfur atoms (atomic mass 32.066 amu) is
96.2 g.
10.7 g.
32.1 g.
6.022 x 1023 g.
How many atoms are present in 40.0 mol of zirconium?
4.82 x 1025 atoms Zr
6.022 x 1023 atoms Zr
2.41 x 1025 atoms Zr
This can't be calculated
How many moles of iron are equivalent to 5.32 x 1026 atoms?
5.32 mol Fe
55.9 mol Fe
6.022 x 1023 mol Fe
883 atoms
Determine the mass in grams of 10.0 mol of chlorine. The molar mass of chlorine is 35.453 g/mol.
355 g Cl
3.54 g Cl
10.0 g Cl
6.022 x 1023 g Cl
Determine the number of moles in 100. g of nitrogen. The molar mass of potassium is 14.01 g/mol.
1400 mol N
2.56 mol N
7.14 mol N
6.022 x 1023 mol N
Calculate the mass in grams of 6.00 mol of potassium (molar mass 39.10 g/mol).
0.153 g K
235 g K
39.1 g K
6.022 x 1023 g K
Calculate the number of atoms in 5.0 g of sulfur (molar mass 32.07 g/mol).
5.0 x 1025 atoms S
32 atoms S
6.022 x 1023 atoms S
9.4 x 1022 atoms sulfur
How many atoms are in a mole of a substance?
6.022 x 1025 atoms
6.022 x 1026 atoms
6.022 x 1023 atoms
12 atoms
The atom is electrically neutral with a net charge of zero.
True
False
Which subatomic particle has a negative charge?
proton
neutron
electron
nucleus
What is the charge of the atom's nucleus?
positive
negative
It has no charge
It can't be detrmined
