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What is 1 + 3?
The effective nuclear charge experienced by an electron in a multi-electron atom increases when the number of nuclear protons increases. True or False?
Screening of the nuclear charge by core electrons in atoms is ________.
more efficient than that by valence electrons.
A tin atom has 50 electrons. Electrons in the __________ subshell experience the lowest effective nuclear charge.
__________ is isoelectronic with argon and __________ is isoelectronic with neon.
Which one of the following has the smallest radius?
Oxides of most nonmetals combine with water to form __________.
The alkali metal that is used to treat manic-depressive illness is __________.
Which noble gas has the lowest first ionization energy?
Which periodic table group contains only nonmetals?