Chapter 5 test Radiation around usName_________________________________________ Section________________________

1. Which nuclei of atom is radioactive?a. stable b. unstable c. helium d. all nuclei

2. Which of the following is correct regarding stability of nuclei?a. nuclei with an even number of neutrons and protons tend to be more stable b. nuclei with more protons than neutrons tend to be more stablec. nuclei with an odd number of both neutrons and protons are stabled. nuclei with an even number of protons but odd number of neutrons tend to be more stable

3. What particle/s from the nucleus are emitted to cause nuclear transformation?a. alpha b. beta c. gamma d. both a and b

4. Which of the following nuclei decays faster?a. uranium 238 with a half life of 4.47 billion yearsb. uranium 234 with a half life of 245000 years c. polonium 218 with a half life of 3.05 minutesd. radon 222 with a half life of 3.823 days

5. The extent of radiation damage inflected by a dose of radiation depends on few things or factors. Which of the following is not a factor?a. dose level and degree of exposureb. organ sensitivity and time length of exposurec. type of radiation and place of habitatd. gender and lifestyle

6. Which of the following is used to date relatively old inorganic samples?a. uranium dating b. carbon dating c. inorganic dating d. old samples dating

7. Which of the following is used to date relatively young plant and animal remains? a. uranium dating b. carbon dating c. inorganic dating d. old samples dating

8. All life forms on earth developed and evolved in the presence of radiation. About how many per cent of annual radiation are we receiving from natural sources?a. 87% b. 78% c. 59% d. 13%

9. The Earth and its inhabitants are bombarded with cosmic and terrestrial radiation. Which among the choices below is referred to as terrestrial radiation?

a. radiation rising from the crust to the earth’s surfaceb. radiation from the earth’s surface into the crust c. radiation manufactured by plants d. none of the above

10. Background radiation levels:a. are constant world-wide, except during times of solar flares.b. decrease with elevation.c. depend on altitude and type of rock or soil in the area.

11. There are a number of types of nuclear radiation, such as alpha, beta, and gamma rays. Gamma radiation is:

a. High energy electronsb. High energy neutrons.c. High energy protons.d. High energy helium nucleie. High energy electromagnetic radiation, similar to light and x-rays.

12. Radiation is created by a process of:

a. atomic decay b. unexplainable forces c. elemental neutralization d. atomic stretching

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13. Ionizing radiation:

a. is always something to be avoided. c. is a new health miracle medicine b. has both benefits and risks d. has no medical or commercial applications.

14. This profession's name was first given during World War II and the profession's goal is to use practical means for protecting people from harmful radiation exposures

a. Economist b. rocket scientist c. radiobiologist d. health physicist

15. The three main types of ionizing radiation are:

a. positive, negative, and neutral c. Uranium, helium, and plutoniumb. alpha, beta, and gamma d. neutrons, positrons and electrons

16. The three basic concepts in radiation protection are

a. exposure, energy, and decay c. exposure, time, and decay b. energy, distance, and shielding d. time, distance, and shielding

17. What percentage of human radiation exposure comes from natural sources? a. 0% b. 20% c. 80% d. 100%

18. Who is the only person ever to receive the Nobel Prize in both chemistry and physics?a. Albert Einstein b. Marie Curie c.Wilhelm Conrad Roentgen d. Enrico Fermi

19. William Conrad Roentgen discovered:a. atoms b. natural radioactivity c. X-rays d. neutrons

20. A radioactive substance has a half-life of 30 minutes. What fraction of the atoms will not have decayed after 1 hour? a. 1/8 b. ¼ c. ½ d. ¾

 21.      Another substance has a half-life of 3 hours. What fraction of the atoms will have decayed after 6 hours?  a. 1/8 b. ¼ c. ½ d. ¾

22. A researcher measures 200 counts per minute coming from a radioactive source at midday(12:00 o’clock). At 3 o'clock, she finds that this has dropped to 25 counts per minute. What is the half-life of the radioactive source?

a. 1 hr b. 2 hrs c. 3 hrs d. 4 hrs

23. You purchased a radionuclide/radioactive material with a 14 day half-life. Eight weeks later, how much is left?

a. 1/16 b. 1/8 c. 1/32 d. 1/2

24. The total damage caused by radioactive material is dependent on:

a. the number of disintegrations per second b. the energy of the decay particle c. the nature of the decay particle d. all of the above

25. You accidentally spill some radionuclide/radioactive material on yourself and it contaminates your skin. You must:

a. call Radiation Safety b. go to the Student Health center c. wash the skin in cold water with hand soap d. first (c) then (a

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……..

U-238

26. What are atoms of the same element having different number of neutrons called?a. radioactive atoms b. stable atoms c. isotopes d. uranium

27. Which nuclei tend to be more stable compared to others?a. nuclei with more neutrons than protons c. nuclei with an even number of protons and neutronsb. nuclei with even number of protons but odd number of neutrons d. nuclei with odd number of both protons and neutrons

28. A radioactive emission that is not deflected by a magnetic field is;a. alpha emission b. beta emission c. gamma emission d. none of the first three

29. When radiation affect the cells , the growth is affected. The change in the growth due to changes in the growth of cells is called;a. genetics b. mutant c. changes d. radiation

20. Radiation dose is a measure of ‘the amount f energy absorbed per kilogram of an irradiated object at the actual target site.” The unit of radiation dose is;a. Sievert b. Becquerel c. Curie d. GrayTest II. 1. The diagram below is a series of radioactive decay rate. The first square is at time 0 with dots representing the total number of radioactive nuclei. Indicate in each successive square the approximate number of remaining nuclei after each half life. Use small dots to indicate the approximate number of radioactive nuclei remaining.

Time: one half life two three four five six seven eight nine

2. Arrange the three types of radioactive emissions according to the criterion specified in the table.From most penetrating to least penetrating

From most ionizing to least ionizing

3. Solve the equations a. 1

1He + 42He _________

b. 258100 Fm 257

100 Fm + __________c. ________ + 0

-1e 24494 Pu

5. Enumerate Applications of Radiation (as many as you can)Use the back space.

3. The circles below indicate the daughter nuclei after the parent nuclei (U-238) would have disintegrated from the type of radiation indicated below the arrow. Fill in the circles with the corresponding daughter nuclei (element) for each radiation indicated. You need a periodic table to complete this part of the test.

.α β β .α α α

α

α β β α β β α

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