1. MIDTERM REVIEW

2. ISOTOPE CALCULATION (5 minutes)
Use the following data to calculate the average atomic mass of “element X” then use the periodic table to identify the element (show all work).
Isotope
Mass (amu)
% Abundance
X-16
15.995
99.762
X-17
16.999
0.038
X-18
17.999
0.20

3. ISOTOPE CALCULATION (5 minutes)
Use the following data to calculate the average atomic mass of “element X” then use the periodic table to identify the element (show all work).
ANSWER:
amu
Oxygen
Isotope
Mass (amu)
% Abundance
X-16
15.995
99.762
X-17
16.999
0.038
X-18
17.999
0.20

4. ISOTOPE CALCULATION (5 Minutes)
What is the atomic mass of hafnium if, out of every 500 atoms, 25 have a mass of 176, 95 have a mass of 177, 135 have a mass of 178, 70 have a mass of 179, and 175 have a mass of 180.0?

5. ISOTOPE CALCULATION (5 Minutes)
What is the atomic mass of hafnium if, out of every 500 atoms, 25 have a mass of 176, 95 have a mass of 177, 135 have a mass of 178, 70 have a mass of 179, and 175 have a mass of 180.0?
ANSWER:
amu

6. Protons, neutrons, electrons (10 minutes)
1. Give the number of protons, electrons, and neutrons in each of the following atoms.
a) Ag
b) Ca
c) Na
2. Name each isotope and write it in hyphen notation and nuclear symbol notation.
a) atomic number 26; mass number 56
b) atomic number 29; mass number 64
c) atomic number 17; mass number 37
3. How many protons, electrons, and neutrons are in each of the following isotopes?
a) uranium-235
b) hydrogen-3
c) silicon-29
d) thorium-230

7. Protons, neutrons, electrons (10 minutes)
1. Give the number of protons, electrons, and neutrons in each of the following atoms.
a) Ag
b) Ca
c) Na
2. Name each isotope and write it in hyphen notation and nuclear symbol notation.
a) atomic number 26; mass number 56
b) atomic number 29; mass number 64
c) atomic number 17; mass number 37
3. How many protons, electrons, and neutrons are in each of the following isotopes?
a) uranium-235
b) hydrogen-3
c) silicon-29
d) thorium-230
p=47, e=47, n=61
p=20, e=20, n=20
p=11, e=11, n=12
5626Fe Iron-56
6429Cu Copper-64
3717Cl Chlorine-37
p=92, e=92, n=143
p=1, e=1, n=2
p=14, e=14, n=15
p=90, e=90, n=140

8. Mass/moles/atoms (20 Minutes)
1. What is the mass of 2.53 moles of lead (II) nitrate Pb(NO3)2
2. Calculate the number of moles in a 3.75g sample of calcium carbide CaC2.
3. Calculate the number of moles in 2.66 x 1022 atoms of potassium iodide.
4. How many molecules are in a 65.6g sample of magnesium chloride.
5. Calculate the mass contained in 15.62x1030 atoms of barium bromide.

9. Mass/moles/atoms (20 Minutes)
1. What is the mass of 2.53 moles of lead (II) nitrate Pb(NO3)2
8.38x102 g Pb(NO3)2
2. Calculate the number of moles in a 3.75g sample of calcium carbide CaC2.
5.85x10-2 mol CaC2
3. Calculate the number of moles in 2.66 x 1022 atoms of potassium iodide.
4.42x10-2 mol KI
4. How many molecules are in a 65.6g sample of magnesium chloride.
4.15x1023 molecules MgCl2
5. Calculate the mass contained in 15.62x1030 atoms of barium bromide.
7.71x109 g BaBr2

10. Density (10 minutes)
1. A rectangular solid of unknown density is 10 cm long, 2 cm high and 4 cm wide.  The mass of this solid is 2.15 × 102 g. Find the density of the solid.
2. A rock has a density of 4 g/mL and a mass of 1.6 × 103 mg.  What is the volume this rock occupies?

11. Density (10 minutes)
1. A rectangular solid of unknown density is 10 cm long, 2 cm high and 4 cm wide.  The mass of this solid is 2.15 × 102 g. Find the density of the solid.
2.69 g/cm3
2. A rock has a density of 4 g/mL and a mass of 1.6 × 103 mg.  What is the volume this rock occupies?
0.4 mL

12. Electron configuration (5 minutes)
1. Write the electron configuration for Silver
2. Write the electron configuration for Tungsten

13. Electron configuration (5 minutes)
1. Write the electron configuration for Silver
2. Write the electron configuration for Tungsten

14. Metric conversions (8 minutes)
1. Convert x 1015 pm = __________ cm
2. Convert 856 cm = ___________ km
3. Convert 3.5x106 µm = ______________ hm

15. Percent error (3 minutes)
A student estimated a mass to be 250 g, but upon carefully measuring it, found the true mass to be 240 g. What is the percent error?

16. Percent error (3 minutes)
A student estimated a mass to be 250 g, but upon carefully measuring it, found the true mass to be 240 g. What is the percent error?

17. Percent mass (8 minutes)
1. A g sample of aspirin is made up of 6.03 g of hydrogen, g of carbon, and g of oxygen. What is the percent by mass of each element in aspirin?
2. A 2.89 g sample of sulfur reacts with 5.72 g of copper to form a black compound. What is the percentage composition of the compound?