Name: _______________________________________ Per:___ Date: ______________ A MODEL ATOM 1. Correctly label the parts of the atom below. 2. Complete the information in the table below Subatomic Particle PROTON NEUTRON ELECTRON Mass Charge Location 3. Choose words from the list below to fill in the blanks in the following sentences comparing atomic number and mass number. The words may be used more than once. atomic number(s) nucleons masses protons mass number(s) isotopes neutron electron o The nucleus consists of _______________________ and ___________________________. o The _________________________________ of an atom gives the number of protons. o The _______________________________________ of an atom gives the number of nucleons (_________________________ and _______________________) in the nucleus. Charles Gailes, CD2, Set 1 Atoms C·R·E·A·T·E for Mississippi Copyright ©2001. All rights reserved. This document may be copied and distributed for nonprofit educational purposes only provided that credit is given to C·R·E·A·T·E for Mississippi. Name: _______________________________________ Per:___ Date: ______________ o The symbols for the elements are often written with the __________________________________ at the upper left and the ________________________________________ at the lower left. For example, the symbol 23 Na represents a sodium atom with a _______________________ of 23 and a ___________________________ of 11. There are 11 ___________________ and 12______________________ in the nucleus of this atom. Since atoms begin neutral (with no overall charge), the number of positive subatomic particles, which are called ______________________ is equal to the number of negative subatomic particles, which are called ______________________, so there are 11 _____________________ as well. o Atoms of the same element may differ in the number of ___________________ in their nuclei. o Atoms that have the same ____________________________________ but different numbers of neutrons are ____________________ of the same element. 3. Fill in the information missing from the following table: Symbol Atomic Number Mass Number Number of Protons Numbers of Electrons Number of Neutrons H 1 1 1 1 0 H 1 3 1 1 2 Na 11 23 B 5 11 1 1 3 1 23 11 11 5 34 S 16 32 S 16 Charles Gailes, CD2, Set 1 Atoms C·R·E·A·T·E for Mississippi Copyright ©2001. All rights reserved. This document may be copied and distributed for nonprofit educational purposes only provided that credit is given to C·R·E·A·T·E for Mississippi.