Subatomic Particles
Name the subatomic particles in an atom, their location, and charge.
Proton + in the nucleus
Electron - outside the nucleus in the cloud
Neutron 0 in the nucleus
The most reactive metals belong to which group? Give the name and number.
Alkali metals - group 1
How many valence electrons does an atom in group 2 have? Group 17?
Group 2 = 2e-
Group 17 = 7e-
Who discovered that protons were present in an atom? What was the name of his experiment?
Ernest Rutherford
Gold foil experiment
What are 2 characteristics of acids?
Acids have a pH of <7
They are often sour, turn litmus paper red, react with metals & carbonates
Why was it more difficult to observe the presence of neutrons in atoms? Give 2 specific reasons.
1. neutrons are not affected by other charged particles in an atom because of their charge
2. Neutrons and protons are both found in the nucleus so it was difficult to observe their behavior independently.
How can you tell which elements will have similar properties to another on the periodic table?
They will be part of the same group of elements.
Draw an electron dot diagram for Lithium (element 3).
Draw an electron dot diagram for Selenium (element 34)
Li in the center with electron on the outside
Se in the center with 6 electrons paired up on the outside
Who discovered that neutrons were present in atoms?
James Chadwick
What are 2 characteristics of bases?
They have a pH of >7
They are often slippery, turn litmus paper blue, bitter
What is an isotope? How many protons, neutrons and electrons are in the following isotope?
Uranium-238
(Be able to do this for any isotope on the periodic table!)
An isotope is an atom of the same element with a different number of neutrons.
U-238 has 92 p+, 92e-, and 146 n
What element is in group 3, period 5?
Y
Which element will most likely form an ionic bond with sodium (Na)? Explain why.
a. potassium (K) b. oxygen (O)
c. fluorine (F) d. aluminum (Al)
C. Fluorine (F) because it is found on the opposite side of the periodic table.
Who is credited with developing the atomic theory?
How much more basic is an material with a pH of 5 than one with a pH of 8?
1000x
How many protons, neutrons, and electrons does phosphorus (P) have?
p+ 15
e- 15
n 16
Which group is the MOST reactive of the nonmetals?
Which is the LEAST reactive?
most: halogens
least: noble gases
How are ionic and covalent bonds different? How are they the same?
Both ionic and covalent bond combine atoms to form compounds.
Ionic bonds transfer electrons. Covalent bonds share electrons.
Who determined that atoms contain electrons?
Who determined that those electrons are in orbits around the nucleus?
JJ Thompson
Niels Bohr
When an acid and a base are combined, what kind of reaction is it? What is formed from this reaction?
Neutralization reaction
A salt and water
Using groups, families, (or in some cases element numbers), identify the location of the following on the periodic table:
1. alkali metals 2. alkaline earth metals
3. transition metals 4. transuranium metals
5. lanthanides 6. actinides
Refer to your periodic table we colored in class!
Draw the line that separates the metals from the nonmetals on your periodic table. Then list the metalloids.
Metalloids are B, Si, Ge, As, Sb, Te, At
Show how Na and O combine ionically.
Show how Se will combine with itself to form Se2.
Na2O - transfer electrons
Se2 will have double bonds.
Who created the first periodic table?
Dmitri Mendeleev
What substances are formed when the acid HI and the base NaOH are combined?
H2O and NaI