Sig Figs
Conversions
Electron Configuration/Periodic Trends
Atomic Number, Mass, and isotopes
Lab Questions
100
How many sig figs are in the following number?:
0.00000089
2
100
49.3 mg to g
0.0493 g or 4.93 x 10-2 g
100
Is Na or Mg larger?
Mg
100
Name the element with the atomic number 54
Xenon
100
What are the units for density?
g/mL OR g/cm3
200
(3.6 x 103) x (6.756 x 107) = ?
24.3 x 1010
200
7.9 mL to cm3
7.9 cm3
200
Is O2- or O smaller?
O
200
How many electrons does the element with an atomic number of 2 and 4 amu have?
2 electrons
200
Emilie had 45.8 g of cosmic brownies. Assume there are 32.0 g of chocolate chips for every 100.0 g of brownies. How many grams of chocolate chips were in my sample?
0 because my roommate stole them.
14.7 g of chocolate chips (theoretically)
300
How many sig figs are in the following number?:
2.300004
7
300
7.82 L to mL
7820 mL or 7.82 x 103 mL
300
Give the condensed electron configuration for Al
[Ne] 3s2 3p1
300
Calculate the atomic mass of an element with 35 protons, 32 neutrons, and 28 electrons
67 amu
300
If Greg had 12.765 g of chocolate chips, transferred them to a bowl, and reweighed them at 11.879 g, what was his percent recovery?
93.059 %
400
7.894-3.2 =
4.7
400
5.937 m to cm
593.7 cm or 5.937 x 102 cm
400
Write the ENTIRE electron configuration of Br
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p5
400
Write the isotopic symbol for an element with an atomic mass of 207 and atomic number of 82
20782Pb
400
Betty adds a copious amount of honey to his hot tea. Which one is the solvent and which one is the solute?
Hot tea is the solvent and honey is the solute
500
9.008/6.435 =
1.400
500
5678 mg to kg
0.005678 kg or 5.678 x 10-3 kg
500
Rank from largest to smallest:
Br-, Cl-, F-, I-
I->Br->Cl->F-
500
how many electrons are in the s, d, and p orbitals?
s: 2 e-
d: 10 e-
p: 6 e-
500
Frankie used a 10-mL graduated cylinder to measure 10.0 mL of water and poured it into
beaker. The mass of the water was 9.678 g. The temperature of water was 24 ° (density= 0.997296g/mL). Find percent error.
(Hint: determine actual volume first)
Actual volume: 9.704 mL
percent error: 2.96%