Dalton's atomic theory agrees with modern atomic theory except for which of these?

atoms are not divided in chemical reactions

Chemical compound has the same elements and same proportions by mass. This statement is of

the law of definite proportions.

Chlorine has atomic number 17 and mass number 35. It has

17 protons, 17 electrons, and 18 neutrons

Which of the following statements is true according to modern atomic theory?

Atoms of the same element may have different masses

An important result of Rutherford's experiments with gold foil was to establish that

the atom is mostly empty space.

# of particles in 1 mole of a pure substance

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Modern Chemistry Chapter 3

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Answers

1
All isotopes of hydrogen contain
two nuclei
one neutron
one proton
two electrons
2
How many neutrons are present in an atom that has an atomic number of 50 and mass of 119?
50
119
69
169
3
Atoms of the same element can differ in
atomic number
number of protons and electrons
mass number
chemical properties
4
The atomic theory proposed by Dalton has been
found to be plagiarized
totally discarded
expanded and modified
accepted unchanged to the present day
5
Dalton's atomic theory agrees with modern atomic theory except for which of these?
atoms of the same element are chemically alike
all matter is made up of small particles
all atoms of the same element have the same mass
atoms are not divided in chemical reactions
6
Isotopes are atoms of the same element that have different
masses
numbers of protons
numbers of electrons
principal chemical properties
7
Chemical compound has the same elements and same proportions by mass. This statement is of
the law of conservation of mass.
The law of multiple proportions.
the law of definite proportions.
the law of isotopes.
8
Which subatomic particle has a charge of +1?
electron
meson
proton
neutron
9
Chlorine has atomic number 17 and mass number 35. It has
35 protons, 35 electrons, and 17 neutrons
17 protons, 17 electrons, and 52 neutrons
18 protons, 18 electrons, and 17 neutrons
17 protons, 17 electrons, and 18 neutrons
10
When elements react to form a compound, the mass of the compound is __ to the mass of elements
less than
equal to
greater than
either greater than or less than
11
The total # of protons and neutrons in the nucleus of an atom is its
average atomic mass
mass number
Avogadro number
atomic number
12
The atomic mass of an element listed in the periodic table is the
atomic mass of the most abundant radioactive isotope
relative atomic mass of the most abundant isotope
mass number of the least abundant isotope
average atomic mass
13
Phosphorus-33 (atomic # 15) contains
18 neutrons
33 neutrons
18 protons
33 protons
14
As atomic # increases, the # of electrons in a neutral atom
increases
decreases
remains the same
is undetermined
15
The average atomic mass of an element is the average of the atomic masses of its
artificial isotopes
naturally occurring isotopes
two most abundant isotopes
radioactive isotopes
16
As the mass # of an element's isotopes of an element increases, the # of protons
decreases
stays the same
increases
doubles each time the mass # increases
17
Which of the following statements is true according to modern atomic theory?
cathode rays are composed of protons
atoms can never combine with any other atoms
atoms may be divided in ordinary chemical reactions
Atoms of the same element may have different masses
18
An important result of Rutherford's experiments with gold foil was to establish that
electrons have a negative charge.
atoms have mass.
neutrons are uncharged particles.
the atom is mostly empty space.
19
The smallest unit of an element that can exist alone is
neutron
atom
proton
electron
20
All atoms of the same element have the same
number of neutrons
mass #
atomic mass
atomic #
21
Avogadro's # is the
max # of electrons that all energy levels can accommodate
# of particles in 1 mole of a pure substance
# of particles in exactly 1 gram of a pure substance
# of protons and neutrons that can fit in the nucleus
22
A nuclear particle that has about the same mass as a proton but no electrical charge is the
isotope
nuclide
electron
neutron
23
The atomic number of an element is the same as the number of
neutrons
protons+electrons
protons
protons+neutrons
24
Which particle has the least mass?
electron
proton
all have the same mass
neutron

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