Chemistry 1 Honors: Test Chapter 3
Calculate the number of neutrons in an atom of Potassium
20
In 1808, John Dalton established his atomic theory. Which of the following is not part of Dalton's atomic theory?
An atom consists of a nucleus and a cloud of electrons.
Which of the following statements of Dalton's atomic theory or Postulates describes conservation of mass?
Atoms cannot be subdivided, created, or destroyed.
In 1913 this scientist discovered that electrons rotated around the nucleus like planets rotate around the sun.
Bohr
Which compound has the largest molar mass?
CO2
Which radioactive isotope is used to treat prostate cancer and brain tumors?
Carbon - 14
Believed that all matter was composed of tiny indivisible particles of Matter that he called "Atomos".
Democritus
Which 2 subatomic particles have relatively the same mass?
Proton and neutron
Believed that all matter was composed of 4 elements; Earth, water, fire and air
aristotle
All atoms of the same element have the same
atomic number
This scientists "Planetary model" is still used today, however it is not the true model. We use it because it is easier to represent the atom in 2D instead of 3D.
bohr
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 ______________________.
conservation of mass.
His 5 postulates helped describe the Law of Conservation of Mass.
dalton
Most of the volume of an atom is occupied by the
electronns
The SI unit of molar mass is the _____.
g/mol
Neutrons have
no charges.
The forces that hold the particles in the nucleus together are called
nuclear forces.
What is the general term for a specific isotope of an element?
nuclide
The isotope of hydrogen called deuterium consists of
one proton, one nuetron, one electron
What unit is used to measure the radius of an atom?
picometer unit
In a Cathode Ray Tube, what is the charge on the anode
positive
What is the charge on an proton?
positive
The atomic number of oxygen, 8, indicates that there are eight
protons in the nucleus of an oxygen atom.
This scientist discovered the nucleus of an atom
rutherford
This scientist is famous for his Gold foil experiment
rutherford
Whose model was Rutherford's experiments trying to support or confirm?
rutherford
An atom's overall charge is electrically neutral because
the numbers of protons and electrons are equal.
What is the name of the isotope of hydrogen that has 1 proton and 2 neutrons?
tritium
When writing an element using its nuclear symbol, what letter is used to represent the atomic number?
z
Isotopes of an element contain different numbers of
neutrons
A balloon contains 7.85 ´ 1021 atoms of helium (He) gas. Calculate the mass of helium in grams.
0.052 g
How many moles are present in 12.5 g hydrochloric acid HCl?
0.343 mol
How many moles of Ag contain 3.17 ´ 1023 atoms Ag?
0.526 mol
How many moles of sodium hydroxide, NaOH, are in a 35.65 g sample of NaOH? (The molar mass of NaOH is 40.01 g/mol.) Responses
0.8910 mol
How many protons are in an atom of deuterium?
1
Determine the mass in grams of 0.025 mol cobalt.
1.47 g
What is the mass of 6.12 mol of glucose, C6H12O6? (The molar mass of C6H12O6 is 180.18 g/mol.)
1102.70 g
How many electrons are in a neutral atom of Silicon?
14 electrons
An oxygen isotope consists of 8 protons, 8 electrons, and 9 neutrons. Its mass number is
17
An atom of potassium has 19 protons, and 20 neutrons. If it is a neutral atom, how many electrons does it have?
19
Zinc-66 (atomic number 30) has
36 nuetrons
Silver-109 has 62 neutrons. The neutral atom has
40
Calculate the relative average atomic mass for the following data:
53.423
The number of atoms in 1 mol of Nitrogen is
6.02 ´ 1023.
Calculate the number of atoms in 16.9 mol copper.
7.95 ´ 1025 atoms
What is the molar mass of Ca(OH)2?
74.092 g/mol
What is the mass in grams of 1.02 ´ 1024 atoms manganese (Mn)?
9.30 ´ 101 g
Which radioactive isotope is used in the treatment of brain tumors?
Iodine-125
He discovered the electron using a device known as a Cathode Ray Tube.
J.J. thomson
Which Law states that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or the source of the compound?
Law of Definite proportions
Which radioactive isotope is used to diagnose and treat thyroid cancer?
iodine-131
This scientist determined the charge of an electron
milikian
This scientist performed investigations using his oil drop experiment.
milikian
A particle in the nucleus that has about the same mass as a proton, but with a neutral electrical charge, is called a(n)
neuton
