MORE QUARTERLY EXAM PRACTICE PROBLEMS 1. Complete each calculation below. Report answers in scientific notation with the correct number of significant digits: a. 0.00325g + 0.098g – 0.02164g = b. 235kg x 33.25m ÷ 64sec2 = 2. There are 197 houses in my neighborhood. Each property has a lot width of 545 feet. I can trick-or-treat at a rate of 5.16 x 109 µm/hr. How many houses can I cover in 115 minutes? Use dimensional analysis to solve! Show unit cancellation. (1 inch = 2.54cm.) 3. Nickel has a density of 8.9 g/cm3. Find the volume of 500 mg of nickel. 4. Determine the half life of a radioactive isotope if a 2800ng sample of the isotope decays to 175ng in 32 minutes. 5. Write the equations for the following nuclear reactions: 154 62𝑆𝑚 - alpha decay ______________________________________________________ 140 56𝐵𝑎 - beta decay _______________________________________________________ 244 94𝑃𝑢 - alpha decay with gamma radiation: __________________________________________ 6. The atomic mass and relative abundance of the isotopes of lead are given in the chart below. Use the data to calculate the average atomic mass of lead. Isotope Atomic mass (amu) 204 Pb Pb 207 Pb 208 Pb 206 203.97 205.97 206.98 207.98 Natural abundance (atom %) 1.4 24.1 22.1 52.4 7. The element boron has two naturally occurring isotopes. 105𝐵 has an atomic mass of 10.00amu, and an atomic mass of 11.01amu. The mass of boron on the periodic table is 10.81amu. Find the relative abundance of each isotope. 11 5𝐵 has 8. Find the wavelength of a photon of light, in nm, if the energy is 3.33 x 10-19J. 9. Find the frequency of energy with a wavelength of 0.0045cm. 10. The data below was collected for two different sized screws, each made from the same type of metal. The volumes of the screws were to be determined by water displacement. Use the data in the table below to determine the final water level for the second screw. Screw # 1 2 Mass 10.25 g 14.47 g Initial Water Level 1.20 mL 5.00 mL 1a. 8.0 x 10-2g b. 1.2 x 102 kg . m/ sec2 2. 59.5 houses 7. 19.80% 10B, 80.20% 11B 8. 597nm Final Water Level 2.50 mL ?? 3. 0.06cm3 4. 8.0 minutes 9. 6.7 x 1012 Hz 6. 207.22amu 10. 6.83mL