CP Chem Atomic Structure Worksheet No. 1
Name____________KEY________________________ Per______
1.The 3 particles of the atom are:
a._________electron_____________
b.________neutron_______
c.________proton________
Their respective charges are:
a._______P (+)_______________
b.________e (-)___________
c.________N (neutral)___________
2.The number of protons in one atom of an element determines the atom’s
____identity__________,and the number of electrons determines
_______charge____________of and element.
3.The atomic number tells you the number of
_______protons___________in one atom of an element. It also tells you
the number of ____electrons___________in a neutral atom of that
element. The atomic number gives the “identity “ of an element as well as
its location on the Periodic Table. No two different elements will have the
___same__________ atomic number.
4.The ______average atomic mass________________of an element is
the average mass of an element ’s naturally occurring atom, or isotopes,
taking into account the _______abundance___________of each isotope.
5.The _____mass number_________________of an element is the total
number of protons and neutrons in the_______nucleus_______________
of the atom.
6.The mass number is used to calculate the number of
________neutrons______________in one atom of an element. In order to
calculate the number of neutrons you must subtract the
_______protons_________from the _mass number_________________.
7.Give the symbol and number of protons in one atom of:
Lithium _________Li - 3_____ Bromine ____Br - 35______________
Iron ________Fe - 26_______
Copper ______Cu - 29____________
Oxygen _______O - 8_______ Mercury _____Hg - 80_____________
Krypton _______Kr - 36________Helium ______He - 2_____________
8.Give the symbol and number of electrons in a neutral atom of:
Uranium _______Ur - 92___________ Chlorine __Cl - 17____________
Boron ___B - 5_______________ Iodine _____I - 53_____________
Antimony _____Sb - 51_____________Xenon _____Xe- 54___________
9.Give the symbol and number of neutrons in one atom of:
(To get “mass number ”,you must round the “atomic mass ” to the nearest
whole number)) Show your calculations.
Barium _____Ba - 81_____________Bismuth ___Bi - 126_____________
Carbon ______C - 6____________Hydrogen _______H - 0___________
Fluorine _______F - 10___________Magnesium ___Mg - 12___________
Europium ________Eu - 89______Mercury ___Hg - 121___________
10.Name the element which has the following numbers of particles:
a. 26 electrons,29 neutrons,26 protons ____Fe_________________
b. 53 protons,74 neutrons ______I_______________
c. 2 electrons (neutral atoms)_______He______________
d. 20 protons ______Ca_______________
e. 86 electrons,125 neutrons,82 protons (charged atom
______Pb______________
f. 0 neutrons _______H______________
11 .If you know only the following information can you always
determine what the element is? (Yes/No).
a. number of protons __Y_________
b.number of neutrons___N________
c.number of electrons in a neutral atom__Y_________
d.number of electrons____N_______