WorksheetsThe Atom: The Building Blocks of Matter Review
Total questions: 20
Worksheet time: 10mins
John Dalton thought that atoms
contain molecules.
cannot be broken down further.
are all composed of carbon.
have no mass.
Using improved chemistry equipment in the late 1700s, chemists observed that mass is neither created nor destroyed in a chemical reaction. This scientific law is called the law of
definite proportions.
gravity.
conservation of mass.
conservation of momentum.
In an experiment, Alex and Rachel discover that their sample of table salt, also known as sodium chloride, NaCl, consists of 39.34% by mass sodium, Na, and 60.66% by mass chlorine, Cl. Later, Alex wonders what the percentage of Na might be in the table salt in his saltshaker at home. Rachel tells him, correctly, that it is
39.34%.
60.66%.
90%.
90%.
The fact that every sample of a particular chemical compound contains the same elements in exactly the same proportions by mass is known as the law of
conservation of energy.
conservation of mass.
atomic theory.
definite proportions.
A molecule of carbon monoxide, CO, has one atom of oxygen while a molecule of carbon dioxide, CO2, has two. In a sample of CO containing 1 g of carbon, 1.33 g of oxygen will combine with the carbon to form the molecule. What is the mass of oxygen in a sample of CO2 containing 1 g of carbon?
1.33g
3.0g
2.66g
0.0g
If two or more compounds are composed of the same two elements, then the ratio of the masses of the second element that is combined with a certain mass of the first element is always a ratio of small whole numbers. This statement is called the law of
definite proportions.
conservation of mass.
atomic theory.
multiple proportions.
In 1808, John Dalton established his atomic theory. Which of the following is not part of Dalton’s atomic theory?
All matter is composed of atoms
An atom consists of a nucleus and a cloud of electrons.
Atoms cannot be subdivided, created, or destroyed.
In chemical reactions, atoms are combined, separated, or rearranged.
Which of the following statements of Dalton’s atomic theory describes conservation of mass?
All matter is composed of atoms.
Atoms of a given element are identical in size, mass, and other properties.
Atoms cannot be subdivided, created, or destroyed.
Atoms of different chemical elements combine in simple whole-number ratios to form chemical compounds.
Which of the following statements of Dalton’s atomic theory describes the law of multiple proportions?
All matter is composed of atoms.
Atoms of a given element are identical in size, mass, and other properties.
Atoms cannot be subdivided, created, or destroyed.
Atoms of different chemical elements combine in simple whole-number ratios to form chemical compounds.
Which is one way that Dalton’s atomic theory has been shown to be incorrect?
Atoms can change identity in chemical reactions.
Atoms can be split into subatomic particles.
Atoms can be destroyed by chemical reactions.
Some atoms of a particular element are identical to atoms of other elements.
Experiments with cathode rays being deflected by a magnetic field show that cathode rays are composed of particles that are
magnetic
negatively charged
positively charged
neutral in charge
Cathode rays are composed of particles that are now known as
positrons
neutrons
protons
electrons
In 1911, Ernest Rutherford conducted his now famous goldfoil experiment. During the experiment, alpha particles bombarded a thin piece of gold foil. The alpha particles were expected to pass easily through the gold foil. Every now and then, however, an alpha particle bounced back—an unexpected result. Rutherford concluded that these particles were striking
a tiny region of positive charge
a dense region of negative charge
a dense region of neutrons
a tiny region with a strong magnetic field
Rutherford called the region that deflected alpha particles
an electron
a positron
a nucleus
a quark
The total volume of the nucleus of an atom is
very large compared with the rest of the atom.
very small compared with the rest of the atom.
about the same size as an electron.
smaller than a neutron.
Except for in the simplest type of hydrogen atom, all nuclei consist of
protons and electrons
neutrons and positrons
protons and neutrons
electrons and positrons
Most of an atom is
dense
fluid
empty
the nucleus
The atomic number of an element is
the mass of the element
1 mol of the element
the number of protons in each atom of the element
the number of neutrons in each atom of the element
Isotopes are atoms of the same element that have different
masses
charges
number of electrons
atomic numbers
Mass number is
the average atomic mass of an element
the total number of electrons in an atom of an element
the total number of protons in an atom of an element
the total number of protons and neutrons in an atom of an element
