Explanation

Explanation

• Gas molecules move freely in all directions because the particles are far apart.
• Gas particles have weak intermolecular forces and high kinetic energy.

Additional information:

• Solids: Vibrate in fixed positions
• Liquids: Move/slide around each other

Last verified on 06-10-2026

Explanation

• Hepta- is the prefix used to represent 7 carbon atoms.
• It is derived from the Greek word hepta, meaning seven.

Additional information:

• 1 = Mono-
• 2 = Di-
• 3 = Tri-
• 4 = Tetra-
• 5 = Penta-

Last verified on 06-10-2026

Explanation

• Sunlight, water, and carbon dioxide are the main requirements for photosynthesis.
• Green plants use chlorophyll to absorb sunlight.

Additional information:

• Glucose is a product of photosynthesis.
• Oxygen is mainly released as a by-product.

Last verified on 06-10-2026

Explanation

• Wavelength is the distance between two successive corresponding points of a wave, such as two crests.
• It can be measured in meters (m), centimeters (cm), and nanometers (nm).
• The SI unit of wavelength is meter (m).
• Nanometer (nm) is commonly used for very short wavelengths, especially in light.

Conversions:

• 1 m = 100 cm
• 1 cm = 10⁻² m
• 1 nm = 10⁻⁹ m

Last verified on 06-10-2026

Explanation

• Human bones are mainly composed of calcium and phosphate, primarily in the form of calcium phosphate.
• Calcium gives bones strength and hardness.
• Phosphate also plays an important role in maintaining strong bones and teeth.
• The major mineral in bone is hydroxyapatite, a calcium-phosphate compound.

Last verified on 06-10-2026

Explanation

• Smog is a combination of smoke and fog.
• The word smog is formed from smoke + fog.
• It is a type of air pollution that reduces visibility and can harm human health.
• Smog is commonly associated with vehicle emissions and industrial pollutants.

Last verified on 06-10-2026

Explanation

• The SI unit of power is the watt (W). 
• A watt is equal to one joule of work done per second. 
• Symbol: W
• Definition: 1 watt = 1 joule per second
• Named after: James Watt

Last verified on 05-10-2026

Explanation

• Cell biology  is a branch of biology that studies the structure, function, and behavior of cells.
• All living organisms are made of cells.
• Also cellular biology or cytology
  

Explanation

• A step-up transformer increases the voltage.
• Output voltage > Input voltage
• It has more turns in the secondary coil than in the primary coil.
• It is used to increase voltage for long-distance power transmission.