CEM 141 MSU Exam 3
Ionization Energy - ✔✔energy required to remove an electron from an atom in the gas phase
Left Side Electrons - ✔✔have weaker attractions to remove electrons *easier to remove electrons from the left side of the table than the right side*
Does it take MORE or LESS energy to remove an electron from Li than from Na? - ✔✔MORE Why? Because as we move down a group, the orbitals become larger and weaker. While going across the effective nuclear charge increases. (holds onto the electrons tighter)
Big Bang evidence - ✔✔universe is expanding (red shift)
Where do atoms come from? - ✔✔The Big Bang
What were elements formed by? - ✔✔Nuclear reactions
Chemical reactions - ✔✔involve rearrangements of valence electrons *the element undergoing a chemical reaction does not ever change*
Ionization energies are affected by - ✔✔-size of an atom -size of positive charge
Periodic Trends - ✔✔-small atoms have higher ionization energies -they are inversely related
Atomic Radius Decreases ----> Ionization energy increases - ✔✔when the radius decreases, it pulls the electrons closer. decreasing the size of an atom
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Nuclear Reactions - ✔✔Fusion and Fission
Fusion - ✔✔two lighter nuclei combines to form a heavier nucleus (energy released)
Fission - ✔✔a heavier nucleus is broken a part to form lighter, more stable nuclei energy
Atomic # = - ✔✔# of protons
Atomic mass = - ✔✔what's left over
Do isolated atoms or molecules have melting or boiling points? - ✔✔No
Do isolated atoms or molecules exist in a state (solid, liquid, gas)? - ✔✔No
Why do bonds form between atoms? - ✔✔because valence electrons are attracted to the nuclei of other atoms
Covalent Bonds - ✔✔two hydrogen atoms interact and form a covalent bond
What properties do metals have? - ✔✔-hard -conduct electricity -shiny -react w/water -malleable
Bonding in Metals - ✔✔atomic orbitals combine with each other to form molecular orbitals
Covalent bonds hold atoms together within.. - ✔✔molecules
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