10th Class Chemistry: Transformations

Physical Transformations

• Physical transformations do not alter the chemical composition of a substance.
• Examples include: melting, freezing, vaporization, condensation, sublimation, and deposition.
• States of matter include solid, liquid, and gas.

Calculating Amount of Substance

• To calculate the number of moles, use the formula: N = m/M, where:

  • N represents the number of entities (molecules)
  • m represents the sample mass (in kg)
  • M represents the mass of a single entity (in kg).

• The number of Avogadro is a constant, NA = 6.02 × 10²³ mol⁻¹

• The number of moles (n) can also be found using n = N/NA

• A 1.5L bottle of water contains approximately 83 moles of water molecules.

Chemical Transformations

• Chemical transformations involve the rearrangement of atoms to form new substances.
• These transformations are represented by chemical equations.
• A balanced chemical equation shows the number of atoms of each element on both sides of the reaction is equal.

Example Equation:

• C₆H₁₂O₆ + 6O₂ → 6H₂O + 6CO₂
  • Glucose (C₆H₁₂O₆) reacts with oxygen (O₂) to produce water (H₂O) and carbon dioxide (CO₂).

Energy Changes in Transformations

• Endothermic transformations absorb heat from the surroundings.
• Exothermic transformations release heat to the surroundings.
• The quantity of energy transferred during a transformation is often expressed in joules (J)

Explore the concepts of physical and chemical transformations in this 10th class chemistry quiz. Understand the processes of melting, freezing, and chemical equations, while also calculating the amount of substances through moles. Test your knowledge and enhance your understanding of these crucial topics!