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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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Isotopes and Mass Number – Definition, Examples, Uses, and Calculation

 Isotopes and Mass Number

What are Isotopes?

Isotopes are different forms of the same element. They have the same number of protons but different numbers of neutrons. This means their atomic number is the same, but their mass number is different.

Examples of Isotopes:

  1. Hydrogen Isotopes:

    • Protium (¹H): 1 proton, 0 neutrons.
    • Deuterium (²H): 1 proton, 1 neutron.
    • Tritium (³H): 1 proton, 2 neutrons.

  2. Carbon Isotopes:

    • Carbon-12 (¹²C): 6 protons, 6 neutrons.
    • Carbon-14 (¹⁴C): 6 protons, 8 neutrons. (Used in carbon dating)

Types of Isotopes

Isotopes are classified into two types:

  1. Stable Isotopes: These do not change over time. Example: Carbon-12, Oxygen-16.
  2. Radioactive Isotopes: These break down over time and emit radiation. Example: Uranium-238, Carbon-14.

Mass Number

The mass number of an atom is the sum of its protons and neutrons.

Formula:


Mass Number = Number of Protons + Number of Neutrons

Example:

  • Sodium (Na)
    • Protons: 11
    • Neutrons: 12
    • Mass Number = 11 + 12 = 23

Uses of Isotopes

Medical Uses

  • Radioactive iodine (I-131) is used to treat thyroid diseases.
  • Cobalt-60 is used in cancer treatment.

Industrial Uses

  • Carbon-14 is used in archaeological dating.
  • Uranium-235 is used in nuclear power plants.

Scientific Uses

  • Oxygen-18 is used in water cycle studies.
  • Hydrogen isotopes help in space research.

Calculation of Relative Atomic Mass

Most elements exist as a mixture of isotopes. To find the relative atomic mass, we use the following formula:


{Relative Atomic Mass} = (m_1 × a_1) + (m_2 × a_2) + ...}{100}

Where:

  • are the isotopic masses.
  • are the percentage abundances of each isotope.

Example Calculation (Chlorine)

Chlorine has two isotopes:

  • Cl-35 (75.77%)
  • Cl-37 (24.23%)

Relative Atomic Mass of Cl = (35 × 75.77) + (37 × 24.23)100


= (2641.95) + (896.51)100


= 35.45 amu

So, the relative atomic mass of chlorine is 35.45 amu.


MCQs on Isotopes and Mass Number

1. What are isotopes?
A) Atoms with the same number of protons but different neutrons
B) Atoms with different numbers of protons and electrons
C) Atoms of different elements with the same mass
D) Atoms with the same atomic and mass numbers

2. Which of the following is an isotope of hydrogen?
A) Oxygen-16
B) Carbon-14
C) Deuterium
D) Sodium-23

3. The atomic number of an element represents the number of:
A) Neutrons
B) Protons
C) Electrons
D) Both protons and neutrons

4. The mass number of an atom is calculated by:
A) Adding protons and electrons
B) Subtracting electrons from protons
C) Adding protons and neutrons
D) Adding electrons and neutrons

5. Carbon-12 and Carbon-14 are examples of:
A) Different elements
B) Isotopes
C) Compounds
D) Ions

6. The isotope Uranium-235 is used for:
A) Treating cancer
B) Generating nuclear power
C) Measuring temperature
D) Making fertilizers

7. What is the mass number of an atom with 8 protons and 9 neutrons?
A) 8
B) 9
C) 17
D) 16

8. The relative atomic mass of chlorine is:
A) 35
B) 37
C) 36
D) 35.45

9. Which isotope is used in carbon dating?
A) Carbon-12
B) Carbon-14
C) Carbon-13
D) Oxygen-16

10. The isotope Iodine-131 is used in:
A) Food preservation
B) Thyroid treatment
C) Plant growth
D) Space research

Short Questions 

  1. Define isotopes with an example.
  2. What is the difference between atomic number and mass number?
  3. How do isotopes of an element differ from each other?
  4. Why is the relative atomic mass of chlorine not a whole number?
  5. Write the names of three isotopes of hydrogen.
  6. How do radioactive isotopes differ from stable isotopes?
  7. Why is Carbon-14 important in archaeology?
  8. What is the formula for calculating relative atomic mass?
  9. Why are some isotopes used in medicine? Give one example.
  10. Explain why isotopes have the same chemical properties.



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