Atomic Models (4)
Q: Who conceived the idea of atoms?
Democritus
Q: Explain how atoms can be electrically neutral even though they contain charged particles.
A: They contain equal numbers of positive protons and negative electrons.
Q: What does the atomic number identify?
A: The number of protons in each atom of the element and its identity.
What is the symbol for principal energy levels?
n
The lowest energy state is referred to as the:
ground state
Q: Which atomic model describes indestructible spheres with their own properties and different masses?
A: Dalton’s model
Q: True or False: Protons and neutrons have the same mass.
A: False, protons have a slightly lower mass.
Q: What does the mass number identify?
A: The sum of protons and neutrons in the nucleus of an atom.
What is the term to describe the normal energy levels found in an unexcited atom?
principal energy levels
The higher energy levels are said to be in a _______ state.
excited
Q: Which atomic model describes negative electrons embedded in positively charged material?
A: Plum pudding model
Q: What is the charge in coulombs of an electron?
A: −1.602 × 10⁻¹⁹ C
Q: What does the atomic mass identify?
A: The weighted average mass of the element’s naturally occurring isotopes.
What is the term to describe how electrons only change in exact amounts? (To change energy levels, an electron must emit or absorb the exact amount of energy between two energy levels.)
quantized
Atoms in their ground state are said to have only up to _____ energy levels.
7
Q: Which atomic model describes a tiny, positively charged nucleus containing most of the mass with electrons arranged around it?
A: Rutherford’s model
Q: What is the charge in coulombs of a proton?
A: +1.602 × 10⁻¹⁹ C
What do you call an atom with the same number of protons but a different number of neutrons, resulting in a different mass number?
An isotope
The Bohr model was only workable for ______ atoms with _______ electron(s).
small; one
What do you call the pattern of colored lines produced from spectroscopy? Each element's is unique.
emission spectrum
Q: What describes the law of definite proportion?
A: Each chemical compound has a unique composition by mass.
Q: Rank the three basic subatomic particles by mass from least massive to greatest.
A: Electron, proton, neutron
What is one way isotopes can be represented?
the element’s name or symbol followed by a hyphen and the isotope’s mass number OR the element's symbol preceded by its mass number as a super script and its atomic number as a subscript
What is the main difference between the Rutherford model and the Bohr model?
The Bohr model showed that electrons traveled in discrete energy levels. (Rutherford model only suggested that electrons were outside the nucleus.)
On the visible light spectrum you drew, which color has the longest wavelength, lowest frequency and lowest energy?
red