Chemistry Exam 140 Questions with Verified
Answers Updated
, Introduction
This document contains 140 CHM 101 Exam 1 questions with
answers covering atomic structure, isotopes, periodic trends,
chemical nomenclature, ionic and molecular compounds, acids,
unit conversions, significant figures, scientific notation,
density, matter and energy, specific heat, and atomic theory.
It also includes mole calculations, Avogadro’s number, molar
mass, percent composition, empirical formulas, and molecular
formulas.
Exam Questions and Answers
What is the average atomic mass (with four sig figs) of silicon
given the following abundance information on the isotopes of
silicon?
Mass number Abundance
Si-28 92.21 %
Si-29 4.70 %
Si-30 3.09 % --- correct precise answer ---28.11
Neon has two isotopes: Ne-20 (having a mass of 20 ) and Ne-
22 (having a mass of 22 ). Given the following abundances of
these isotopes in nature, what is the average atomic mass of
neon with three sig figs?
Mass number Abundance
Ne-20 90%
, Ne-22 10% --- correct precise answer ---20.2
What is the name for an element that has different masses?
Enter the word only. --- correct precise answer ---isotope
The name for NaF is --- correct precise answer ---sodium
fluoride
The name for AlN is --- correct precise answer ---Aluminum
nitride
The name of AgS is --- correct precise answer ---Silver (II)
sulfide
What is the name of CuO? --- correct precise answer ---Copper
(II) oxide
Which one of the formulas below are one of the 'common
exceptions' for naming?
A) NaCl
B) CuCl
C) CsCl
D) MgCl2 --- correct precise answer ---A
The chemical name for water is --- correct precise answer ---
dihydrogen monoxide