What is the charge of a proton?
positive
In a Bohr model, what particles are shown in energy levels around the nucleus?
electrons
One isotope is 25% abundant. Write its percent abundance as a decimal.
0.25
The atomic number of an element equals the number of:
protons
Which subatomic particle has no charge?
Neutron
How many electrons can the first energy level hold?
2
Convert an abundance of 8% to a decimal for use in an average atomic mass calculation.
0.08
An element has 10 protons, 8 neutrons, and 9 electrons. What is the element?
Neon
Which particle(s) can be found in the electron cloud?
electrons
A neutral atom has 12 protons. How many electrons should you draw in its Bohr model?
12
An element has two isotopes: 10 amu at 50% abundance and 12 amu at 50% abundance. What is its average atomic mass?
11
An atom has 11 protons, 12 neutrons, and 11 electrons. What is its mass number?
23
Which subatomic particle is NOT counted to find the mass of an atom?
Electron
A Bohr model shows 2 electrons in the first level and 7 in the second. What element is represented?
Flourine
An element has isotopes of 24 amu (80%) and 26 amu (20%). Calculate its average atomic mass.
24.4
An atom has 14 protons, 15 neutrons, and a charge of -1. How many electrons does it have?
15
An atom has 17 protons, 18 electrons, and 18 neutrons. Name the element and state whether the charge is neutral, positive, or negative.
Chlorine, negative
A neutral atom has 16 electrons. How many occupied energy levels does its Bohr model have, and how many electrons are in its outermost level?
3 energy levels and 6 valence electrons
Isotope A has a mass of 10 amu and is 60% abundant. Isotope B has a mass of 11 amu and is 40% abundant. Find the average atomic mass.
10.4
Which of the following has 30 neutrons?
Fe-54
Fe-56
Fe-57
Fe-58
Fe-56