Tiny Stuff, Big Problems
Which subatomic particle determines the identity of an element?
Protons
Which element is
1s² 2s² 2p⁶
Neon
What key idea do both the Bohr model and the quantum model share about electrons?
Electrons occupy specific energy levels around the nucleus
When an atom absorbs energy, electrons move to what state?
Excited state
How does atomic radius change down a group?
It increases
Which subatomic particle changes to create ions of the same element?
Electrons
What happens to an atom’s electron configuration when it forms a positive ion?
The atom loses one or more electrons
What does the Bohr model use to describe where electrons are found?
Fixed circular orbits at set energy levels
What electron motion produces the colored light in a flame test?
Electrons dropping to lower energy levels
How does ionization energy change across a period?
It increases
Where are protons and neutrons located in an atom?
In the nucleus
An atom loses one electron to form an ion with the electron configuration
1s² 2s² 2p⁶. What element formed this ion?
Sodium
How does the quantum model describe electron location differently than the Bohr model?
It describes regions of probability called orbitals rather than fixed paths
Unique emission spectra result from differences in what?
Each element has unique energy level spacings
Why do elements in the same group have similar properties?
They have the same number of valence electrons
Which subatomic particle changes to create different isotopes of the same element?
Neutrons
An ion has the same electron configuration as neon and a 2+ charge. What element formed this ion?
Magnesium
Which group of elements typically has properties between metals and nonmetals because of their electron behavior?
Metalloids
Electrons ejected by light hitting a metal demonstrate what effect?
Photoelectric Effect
Why are Group 1 metals more reactive than Group 2 metals?
They lose one valence electron more easily
Two isotopes exist, but one is much more abundant. The atomic mass is closer to what?
More abundant isotope
Which two elements are exceptions to the expected electron configuration due to extra stability from half-filled or fully filled sublevels?
Chromium and copper
Why do metals tend to lose electrons while nonmetals tend to gain electrons?
Metals have fewer valence electrons and weaker attraction to them, while nonmetals have stronger attraction to electrons
Below threshold frequency, why are no electrons ejected?
Low energy
Why do nonmetals attract electrons more strongly across a period?
Higher effective nuclear charge (Zeff)