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Digestive System Disorders: Causes, Symptoms, Treatment & Prevention Guide

Disorders of the Digestive System - Causes, Symptoms & Treatment Disorders of the Digestive System: Causes, Symptoms, Treatment & Prevention 1. Introduction to Digestive Disorders The digestive system breaks down food and absorbs nutrients. Disorders like acid reflux, IBS, or ulcers can interfere with these processes. Understanding symptoms, causes, and treatments is essential for maintaining gut health. 2. Common Digestive System Disorders Acid Reflux (GERD): Stomach acid flows into the esophagus causing heartburn. Peptic Ulcers: Open sores in the stomach or small intestine. Irritable Bowel Syndrome (IBS): Affects bowel habits with cramping and bloating. Constipation: Infrequent or painful bowel movements. Diarrhea: Loose, frequent stools. Inflammatory Bowel Disease (IBD): Includes Crohn's disease and ulcerative colitis. Gallstones: Block bile flow, causing pain an...
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Class 9 Chemistry chapter 2 Short Question Answers of atomic structure

 Short Questions Answers

  • i. Why is it said that almost all the mass of an atom is concentrated in its nucleus?
    • The nucleus contains protons and neutrons, which are much heavier than electrons. Electrons, which make up most of an atom's volume, have negligible mass compared to protons and neutrons.
  • ii. Why are elements different from one another?
    • Elements are defined by the number of protons in their atoms (the atomic number). Each element has a unique number of protons, which determines its chemical properties.
  • iii. How many neutrons are present in ²¹⁰Bi?
    • To find the number of neutrons, subtract the atomic number (number of protons) from the mass number. Bismuth (Bi) has an atomic number of 83. So, 210 - 83 = 127 neutrons.
  • iv. Why is tritium (³H) a radioactive element?
    • Tritium has an unstable nucleus due to an imbalance of protons and neutrons. This instability causes it to undergo radioactive decay to achieve a more stable configuration.
  • v. How can an atom absorb and evolve energy?
    • Atoms can absorb energy, causing electrons to jump to higher energy levels. When electrons return to lower energy levels, they release energy in the form of photons (light).

3. Constructed Response Questions

  • i. Why does the energy of electron increase as we move from the first shell to the second shell?
    • Electron shells further from the nucleus have higher energy levels. Electrons in outer shells are less tightly bound to the nucleus and therefore possess more potential energy.
  • ii. Why is it needed to lower the pressure of the gas inside the discharge tube?
    • Lowering the pressure reduces the number of gas molecules, allowing electrons to travel farther without colliding with other molecules. This makes it easier to observe the behavior of electrons.
  • iii. What is the classical concept of an electron? How has this concept changed with time?
    • Classically, electrons were thought of as particles orbiting the nucleus like planets around the sun. However, with the development of quantum mechanics, electrons are now understood to exhibit wave-particle duality and exist in probability clouds (orbitals).
  • iv. Why are the nuclei of radioactive elements unstable?
    • Radioactive nuclei have an unfavorable ratio of protons to neutrons, leading to instability. They undergo radioactive decay to achieve a more stable configuration.
  • v. During discharge tube experiments, how did the scientists conclude that the same type of electrons and protons are present in all the elements?
    • Regardless of the gas used in the discharge tube, the same negatively charged particles (electrons) were emitted. Also, the properties of protons were consistent between different elements. This consistency led to the conclusion that these subatomic particles are fundamental to all atoms.

4. Descriptive Questions

  • i. Explain the structure of a hydrogen atom.
    • A hydrogen atom consists of a single proton in its nucleus and a single electron orbiting the nucleus. It is the simplest atom.
  • ii. How does the theory of atomic structure explain the ionization of atoms by a radioactive isotope?
    • Radioactive isotopes emit ionizing radiation (e.g., alpha, beta, gamma). This radiation can knock electrons out of atoms, creating ions.
  • iii. What is radioactivity? Explain any three applications of radioactive isotopes.
    • Radioactivity is the spontaneous emission of particles or energy from an unstable nucleus.
      • Medical imaging: Radioactive isotopes are used as tracers to diagnose medical conditions.
      • Carbon dating: Carbon-14 is used to determine the age of organic materials.
      • Cancer treatment: Radiation therapy uses radioactive isotopes to destroy cancer cells.
  • iv. Find out the relative atomic mass of mercury from the following data.
    • To find the relative atomic mass, you would multiply the mass of each isotope by its relative abundance, and then add those results together. Because the exact mass of each Isotope is not given, only the relative abundance, it is impossible to give a totally correct answer. If the mass of the isotopes were all very close to 200, then you could simply add all the percentages together, and then divide by 100, and multiply the result by 200. This question is missing data to be answered correctly.

5. Investigative Questions

  • i. How can scientists synthesize elements in the laboratory?
    • Scientists can synthesize elements by bombarding atomic nuclei with particles in accelerators. This can cause nuclear reactions that create new elements.
  • ii. A system just like our solar system exists in an atom. Comment on this statement.
    • The analogy is that electrons orbit the nucleus like planets orbit the sun. However, this is a simplified view. Electrons behave according to quantum mechanics and do not follow fixed orbits like planets.


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