PhySci U3 QC
How many neutrons are in the isotope carbon-14
8 Explanation: (atomic mass 14 - atomic number 6 = 8)
Which statement about electrons and atomic orbitals is NOT true? *An electron has the same amount of energy in all orbitals. *An orbital can contain a maximum of two electrons. *An electron cloud represents all the orbitals in an atom. *An atom's lowest energy level has only one orbital.
An electron has the same amount of energy in all orbitals.
Statement that best describes Rutherford's model of the atom
It is like a huge stadium with a positively charged marble at the center.
Which statement about subatomic particles is NOT true? *Protons and neutrons have almost the same mass. *Protons and electrons have opposite charges. *Unlike protons and electrons, neutrons have no charge. *Protons and neutrons have the same charge.
Protons and neutrons have the same charge.
What part of Rutherford's investigations demonstrated that the Thomson model was not accurate?
They showed that the atoms have a dense nucleus.
The Greek philosopher Democritus coined what word 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
Which element has 17 protons, 17 electrons, and 18 neutrons?
chlorine Explanation: atomic mass minus atomic number 35 - 17 = 18
J. J. Thomson's experiments provided evidence that an atom
contains negatively charged particles.
Which subatomic particle has a negative charge?
electron
In Niels Bohr's model of the atom, electrons move
like planets orbiting the sun.
The glowing of a neon light is caused by electrons emitting energy as they
move from higher to lower energy levels.
When an atom is in an excited state,
one or more electrons have moved from the ground state to a higher energy level.
What do scientists use to predict the locations of electrons in atoms?
probability
According to John Dalton's observations, when elements combine in a compound,
the ratio of their masses is always the same.
