In thin demonatration, what instrument was used to meawure radioactivity? Elevoer COUinicy 2. What element was ysed to make the numbers of the watch glow in the dark? 3. A) Two forms of radition are produced by this element. What are they? element number 88 B. Watch the Concepts of hotepes and anver questions pertaining to it: 1. What subatomic particles affect the muss of an atom? a. Protons b. Neutrons c. Elections d. Protons and Nevirons e. Neutrons and flectrons 2. Which hotope of Hrdeogen was the heaviest? Why, what causes it to be hewier than the others?
, Hs donsify c. Watch the Radiation of Objects and answer questions pertaining teit: 1. What was the element that was measured in the fertilizer? 2. What was the element that was measured in the camping lantern? 3. A) What was the element that was measured in the smoke detector? B) What kinds of radiation does this element emit? C) What happened when the paper was placed between the instrument and the smoke detector? How is this result used in smoke detectors in homes?
The Correct Answer and Explanation is:
Part A: Week 10 Assignment – Correct Answers
1. In the thin demonstration, what instrument was used to measure radioactivity?
➡️ Geiger Counter
2. What element was used to make the numbers of the watch glow in the dark?
➡️ Radium
3. A) Two forms of radiation are produced by this element (element number 88). What are they?
➡️ Alpha and Gamma Radiation
Concepts of Isotopes
1. What subatomic particles affect the mass of an atom?
➡️ d. Protons and Neutrons
2. Which isotope of Hydrogen was the heaviest? Why? What causes it to be heavier than the others?
➡️ Tritium (³H) – It is heaviest because it has two neutrons in addition to one proton, increasing its mass.
Radiation of Objects
1. What was the element that was measured in the fertilizer?
➡️ Phosphorus
2. What was the element that was measured in the camping lantern?
➡️ Thorium
3. A) What was the element that was measured in the smoke detector?
➡️ Americium-241
B) What kinds of radiation does this element emit?
➡️ Alpha radiation
C) What happened when the paper was placed between the instrument and the smoke detector? How is this result used in smoke detectors in homes?
➡️ The alpha radiation was blocked by the paper, causing the detector’s reading to drop. This is how smoke detectors work—when smoke enters the chamber, it disrupts alpha particles, triggering the alarm.
300-Word Explanation
Radioactivity is the spontaneous emission of particles or energy from unstable atomic nuclei. To detect such emissions, scientists commonly use a Geiger counter, an instrument that clicks or displays counts per second based on the presence of radiation. This device is crucial in experiments involving radioactive elements.
One historical use of radioactive elements was in luminous watch dials. These dials glowed due to the inclusion of radium (element 88). Radium is radioactive and emits alpha and gamma radiation. The alpha particles excite phosphors mixed with the paint, causing the glow.
Understanding isotopes involves looking at atoms of the same element with different numbers of neutrons. The mass of an atom is mainly determined by protons and neutrons—electrons are too light to make a significant contribution. Hydrogen has three isotopes: protium (1 proton), deuterium (1 proton + 1 neutron), and tritium (1 proton + 2 neutrons). Tritium is the heaviest because it contains the most neutrons.
Radioactive elements are present in everyday items. For example, phosphorus is found in fertilizers, thorium in camping lantern mantles, and americium-241 in smoke detectors. Americium-241 emits alpha radiation, which doesn’t travel far and can be blocked by paper or skin. In smoke detectors, alpha particles ionize air, allowing a small current to flow. When smoke enters the chamber, it interrupts this current, triggering the alarm.
This practical use of radiation demonstrates both the dangers and benefits of radioactive materials in our daily lives. Through careful application, radioactive elements can serve critical roles in health, safety, and industry.
