A
The diameter of a carbon atom is 0.000000000154 m. What is this number expressed in scientific notation?
1.54 x 10^-10 m
Which one has 3 significant figures?
0.000012
1.000001
2.3 x 10^3
0.00000121
0.00000121
What metric prefix corresponds to 0.001?
Milli
What is the density of an object having a mass of 7.2 g and a volume of 30 mL?
0.24 g/mL
What has a shorter wavelength: microwave or visible?
Visible
What is the wavelength of a gamma-ray with a frequency of 2.73 x 10^20 Hz?
1.10x10^-12 m
What do the elements in the same period have in common?
Same number of energy levels
Period # = # of energy levels
How does an electron go from its ground state to an excited state?
Absorbs energy
How many meters are in 1.23 cm?
0.0123 m
What is the definition of the aufbau principle?
Electrons fill atomic orbitals starting from the lowest energy levels before moving to higher ones
What does the orbital diagram for K look like?
1s2 = 1 box w/ 2 arrows
2s2 = 1 box w/ 2 arrows
2p6 = 3 boxes w/ 6 arrows
3s2 = 1 box w/ 2 arrows
3p6 = 3 boxes w/ 6 arrows
4s1 = 1 box w/ 1 up arrow
Number of protons
What are the shapes of the s, p, and d orbitals?
sphere, dumbbell, clover
Student A 2.632 2.725 2.660
Student B 1.532 1.525 1.562
Student C 2.132 1.525 2.306
Actual= 2.699 g/cm^3
Which student is the most precise?
Student B
What type of elements will lose their electrons to form cations? What type of elements will gain electrons to form anions?
Metals will lose electrons to form cations
Nonmetals will gain electrons form anions
What is the electron configuration building order through 6s?
1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s
What is the atomic radius trend across a period? Down a group?
Period: Decreases
Group: Increases
Who was the first to suggest to existence of atoms?
Democritus
What is the difference between an isotope and an ion?
Isotope= same element but different # of neutrons, changes mass
Ion= same element but different # of electrons, changes charge
A train travels at a speed of 10 miles per hour. If 1 mile = 1.6 kilometers, how fast is the train traveling in kilometers per minute?
0.268224 km per minute
What is 30 mph worth in meters per second?
13.4112 meters per second
What ionic charge will Na form? C? S?
Na 1+
C 4-
S 2-
How would you categorize the following into metals, nonmetals, and metalloids?
H, Ba, Xe, Ga, O, B, Zn, Si
Metals: Ba, Ga, Zn
Nonmetals: H, Xe, O
Metalloids: B, Si
What group name for group 1? Group 2? Groups 3-12? Group 17? Group 18?
Group 1: Alkali Metals
Group 2: Alkaline Earth Metals
Groups 3- 12: Transition Metals
Group 17: Halogens
Group 18: Noble Gases
Who originally organized the periodic table and how? How is the periodic table organized today?
Mendeleev: Increasing atomic mass
Now: Increasing atomic number