Download Atoms and the Particles They Contain Chemistry Packet: Honors

Atoms and the Particles They Contain
Chemistry Packet: Honors Biology
Atoms consist of a central part called the nucleus surrounded by an area called the “electron cloud.” There are
three subatomic particles that make up an atom: the protons, neutrons, and electrons.
Protons are found in the nucleus of an atom. They are positively charged and have a mass of 1 amu (atomic mass
unit).
Neutrons are also found in the nucleus of an atom. Neutrons are neutral with no charge and have a mass of 1 amu,
just like the proton.
Electrons are found constantly moving around the nucleus in a random fashion. For teaching purposes we say that
electrons travel in electron clouds or energy levels around the nucleus. Each level has a maximum number of
electrons that it can hold. The first level can hold up to 2 electrons and the other levels can hold up to 8 electrons.
Electrons are negatively charged particles that have very little mass (negligible). An atom’s number of electrons is
equal to its number of protons…because of this, atoms are neutral.
A Neutral Atom: has equal numbers of protons and electrons.
An Ion: has an unequal number of protons and electrons. It is a positive ion if it has more protons than electrons
and it is a negative ion if it has more electrons than protons.
An Isotope: is a heavier form of an atom because it contains additional neutrons.
Atomic Number: is equal to the number of protons in an atom (ex: Carbon (C) contains 6 protons, it’s atomic
number is 6).
Atomic Mass: equals the total number of protons and neutrons in an atom (ex: Carbon (C) has 6 protons and 6
neutrons so its atomic mass is 12).
If you don’t know how many neutrons an atom has, you can use this formula…
Number of Neutrons = Atomic mass- Atomic number
The chart below contains information about two elements. Below the chart, draw a diagram of the atoms that
make up both elements. Show the number and location of the protons, neutrons, and electrons. Example below.
Number of Electrons in the “electron shells”
1 2 3 4 5 6 7
Element
Atomic
Number
Atomic
Mass
Calcium
20
40
2
8
Neon
10
20
2
8
Example:
8
2
Fill out the chart below with what you now know:
Subatomic Particle
Charge of Particle?
Mass of Particle?
Proton
Neutron
Electron
1.
Describe an easy way to determine how many protons are in the nucleus of an atom:
2. Describe an easy way to determine the atomic mass of an atom:
3. Describe an easy way to determine the number of neutrons that are in the nucleus of an atom:
4. Use the words from this word bank below to answer the questions that follow (can be used more than
once):
Atom Atomic mass
Atomic number
Ion
Nucleus
Electrons Isotope
Neutral Atom
a.
Neutrons
Protons
The center of the atom is the _____________
b. The center of the atom contains two particles _______________ and _________________
c. Positively charged atomic particles are called _____________________________
d. Negatively charged atomic particles are called ____________________________
e. All of the mass of an atom is found in its ________________________________
f.
An atom that has equal numbers of protons and electrons is a(n)_________________________________
g. An atom that has an unequal number of protons and electrons is a(n)_____________________________
h. If an atom has extra neutrons, it is called a(n) ______________________________________
i.
The number of protons in an atom represents that atom’s _________________________________
j.
These particles do NOT contribute to the atom’s charge __________________________________
k. These particles do NOT have a significant contribution to the atom’s mass____________________
l.
Atomic mass is equal to the sum of that atom’s _________________ & ___________________
m. If an atom’s atomic number is 20, then it has 20 of these particles ___________________________
n. A neutral atom that has 14 protons also has 14 ________________________________________
o. A heavier form of an atom is called an ________________________________
5. Read through all definitions presented so far. With the information given to you, you will be able to finish
filling out the table below accurately:
Element
Aluminum (Al)
Bromine (Br)
Carbon (C)
Carbon (C)
Helium (He)
Hydrogen (H)
Hydrogen (H)
Lithium (Li)
Nitrogen
Oxygen (O)
Oxygen (O)
Potassium (K)
Atomic
Number
Atomic
Mass
13
Number of
Protons
Number
of
Neutrons
35
45
6
27
6
6
2
1
Number of
Electrons
13
36
6
6
14
4
1
7
14
16
18
39
8
Neutral Atom
Neutral Atom
Neutral Atom
1
3
Pick One:
Isotope?
Ion?
Neutral Atom?
0
2
Neutral Atom
6
8
8
19
Neutral Atom
6. The Chemistry of Life: Living matter is composed of many different elements. Elements are made up of
atoms. The table below shows facts about the six elements that make up most of your body. Use the info
about the atoms and the facts in the table below to answer the questions that follow:
Element
Element
Symbol
Atomic
Number
Atomic Mass
Percent of human body
Hydrogen
H
1
1
9.5
Carbon
C
6
12
18.5
Nitrogen
N
7
14
3.0
Oxygen
O
8
16
65.0
Phosphorous
P
15
31
1.0
Sulfur
S
16
32
0.3
a.
b.
c.
d.
e.
What is the most abundant element in the human body?_________________________________
What is the symbol of the element in question 1? What is its atomic number?________________________
What element makes up 18.5% of the human body?_____________________________
How many protons does Phosphorous have?_________________
Fill in the blanks in this word equation:
Atomic mass = number of _______________ + number of ___________________
f. How many neutrons are in the nucleus of a Nitrogen atom?_____________________
g. Write the symbol of the element found in 0.3% of the human body________________
h. Which element in the chart has no neutrons?______________________
i. How many positive charges are in the nucleus of a carbon atom?_________________________
Counting Atoms:
The formula for a compound indicates the elements that make up the compound and the number of atoms of
each element present in the compound. These numbers of atoms are indicated by the use of small numbers
called subscripts. When a subscript appears outside the parentheses, it indicates that all the elements inside the
parentheses should be multiplied by that subscript. For example, the formula Fe(OH)3 indicates the
combination of one atom of iron, Fe, three atoms of Oxygen, O, and three atoms of Hydrogen, H.
In the following examples, list each element in the compound and the number of atoms of each element present.
The first example has been done for you:
Name
Calcium carbonate
Use
Formula
Limestone
CaCO3
Aspirin
Pain reliever
C9H8O4
Trinitrotoluene (TNT)
Explosive
C7H5(NO2)2
Pyrite
Fool’s gold
FeS2
Sulfuric Acid
Used in car batteries
H2SO4
Iron Oxide
Rust
Fe2O3
Butane
Lighter fluid
C4H10
Silicon Dioxide
Sand
SiO2
Asbestos
Insulator
H4Mg3Si2O9
Calcium dihydrogen
phosphate
Fertilizer
Ca(H2PO4)2
Atoms in Formula
Calcium = 1
Carbon = 1
Oxygen = 3