Chem 201 Final Exam Study Guide questions and answers complete solution 100% 2024/ 2025

Chem 201 Final Exam Study
Guide
any pure substance that is not a mixture and is not a compound must be an
element
the elements that comprise a compound can only be separated from one another by a
chemical reaction
which of the following is an example of a semi metal or matalloid?
a)phosphorus
b)selenium
c)tellurium
d)gallium
e)all of the above
tellurium
matter is anything that
has mass and occupies space
the spontaneous emission of radiation from an unstable nucleus is called
radioactivity
the number of neutrons in uranium-235 is
a)3
b)92
c)142
d)145
e)none of the above
none of the above
the atomic mass of an element represents
the weighted average of the mass of the naturally occurring isotopes
the molar mass of of NaCl is equal to
a)the mass of one mole of NaCl
b)the mass of 6.02 x 10²³ formula units of NaCl
c)the mass of 6.02 x 10²³ atoms of sodium plus 6.02 x 10²³ atoms of chlorine
d) 58.443g per mole
e)all of the above
all of the above
what is the density of a material whose volume is 100.0cm³ and mass is 98.0g?
9.80g/cm³
which of the following is an alkali earth ion?
a)Ca²⁺
b)Mn³⁺
c)P³⁻
d)none of the above
Ca²⁺
the mass number of an element represents