Potassium has an atomic number of 19.
which of a potassium atom's electrons are its valence electrons?
select one:
a. those in the third shell from the nucleus.
b. those in the second shell from the nucleus.
c. those in the outermost shell.
d. those in the innermost shell.

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Ageochemist examines a piece of metal that he found in the soil. he performs tests to identify the metal from its density, electrical conductivity, and melting point. which statement best describes his investigation? a. he is determining physical properties that are sufficient to identify the metal.b. he is determining chemical properties that are sufficient to identify the metal.c. he is determining physical properties that are insufficient to identify the metal.d. he is determining chemical properties that are insufficient to identify the metal.

What atom has the largest atomic radius