physical science chapter 4

If 2 grams of element X combine with 4 grams of element Y to form compound XY, how many grams of element Y would combine with 14 grams of X to form the same compound?

28 grams

which statement about subatomic particles is true

An electron has far less mass than either a proton or neutron

according to _______ all matter was made up of four elements - earth air fire water

Aristotle

Who provided evidence for the existence of a nucleus in an atom?

Ernest Rutherford

which of the following provides the best analogy for an electron in an atomic orbital

a bee trying to escape from a closed jar

which of the following most accurately represents John Dolton's model of the atom

a tiny, solid sphere with predictable mass for a given element

in Rutherford's gold foil experiment, some of the __________ aimed at gold atoms bounced back suggesting that a solid mass was at the center of the atom

alpha particle

which statement about electrons and atomic orbitals is not true

an electron has the same amount of energy in all orbitals

the greek philosopher Democritus coined what word for a tiny for a tiny piece of matter that cannot be divided

atom

the number of protons in one atom of an element is that element's

atomic number

to find the numbers of neutrons in an atom of an atom, you would subtract

atomic number from mass number

Unlike Democritus, Aristotle did not believe that matter was composed of tiny, indivisible_______

atoms

which of the following is NOT part of John Dalton's atomic theory

atoms contain subatomic particles

the moving blades of an airplane propeller provided an analogy for the electron _______ model

cloud

Jhon Dalton observed that elements always combine in the same ratio to form a particular ________

compound

in an atomic model that includes a nucleus, positive charge is

concentrated in the center of the atom

J.J. Thomson's experiments provided evidence that an atom

contains negatively charged particles

Which subatomic particle has a negative charge?

electron

in Bohr's model of the atom,_______ move in fixed orbits around the nucleus

electrons

when an atom gains or loses energy, some of its _________ may move between energy levels

electrons

which statement accurately represents the arrangement of electrons in Bohr's atomic model

electrons travel around the nucleus in fixed energy levels with energies that vary from level to level

John Dalton concluded that all the atoms of a single _____ have the same mass.

element

at atom in which an electron has moved to a higher energy level is in a _______state

exited

when all the electrons in an atom are in orbitals with the lowest possible energy, the atom is in its ______ state

ground

How was Bohr's atomic model similar to Rutherford's model?

it described a nucleus surrounded by a large volume of space

which statement best describes Rutherford's model of the atom

it is like a huge stadium with positively charged marble at the center

in Niels Bohr's model of the atom, electrons move

like planets orbiting the sun

the _______ _____ of an isotope is the sum of the number of protons and neutrons in its nucleus

mass number

the glowing neon light is caused by electrons emitting energy as they

move from higher to lower energy levels

the subatomic particle that J.J. Thomson discovered has a ________ charge

negative

the difference between a sample of heavy water and regular water is that hydrogen atom in the heavy water has an extra _______

neutron

Protons and______are found in the nucleus of an atom.

neutrons

the nuclei of isotopes contain different numbers of _______

neutrons

the diagram in figure 4-1 shows the results of Rutherford's gold foil experiment. what caused some of the alpha particles to bounce straight back from the gold foil

nuclei in the gold atoms

in Rutherford's gold foil experiment, shown in figure 4-1, alpha particles that bounce straight back from the foil have struck ___________ in the gold atoms

nucleus

If element Q has 11 protons, its atomic ____________________ is 11.

number

the region in which an electron is most likely to be found is called an _______

orbital

What do scientists use to predict the locations of electrons in atoms?

probability

Neutrons and ____________________ have almost the same mass.

protons

which statement about subatomic particles is NOT true

protons and neutrons have the same charge

Democritus thought that matter was made of tiny particles

that could not be divided

what is the difference between an atom in the ground state and the exited state

the atom in the exited state has more energy and is less stable then an atom in the ground state

What can you assume has happened if an electron moves to a higher energy level?

the electron has gained energy

what does the electron cloud model describe

the most likely locations of electrons in atoms

which of the following is unique for any given element

the number of protons

Suppose an atom has a mass number of 23. Which statement is true beyond any doubt?

the number of protons in the nucleus does not equal the number of neutrons

according to Jhon Dalton's observations, when elements combine in a compound

the ratio of their masses is always the same

Rutherford's Gold Foil Experiment provided evidence for which of the following statements

there is a dense, positively charged mass in the center of the atom

which statement is true about oxygen-17 and oxygen-18

they are isotopes of oxygen