Explanation

• The reactants in the reaction are Methane (CH4) and Oxygen (O2).
• These two substances combine to form the products Carbon Dioxide (CO2) and Water (H2O), releasing energy in the process.

Explanation

65% of the human body is oxygen.

Oxygen is a major component of water.

It makes up a significant portion of body mass.

Explanation

A refracting telescope has two lenses:

1. A primary lens (objective) that collects and focuses light.
2. A secondary lens (eyepiece) that magnifies the focused light to form an image.

Explanation

• In a mercury thermometer, the mercury in the bulb expands and rises in the tube, which has a linear scale ranging from 35°C to 42°C.
• This range is typically used for medical thermometers to measure human body temperature.

Explanation

• Aerosols are a type of mixture where solid particles or liquid droplets are suspended in a gas, like air.
• Examples of aerosols include mist, fog, dust, pollen, and spray cans.

Explanation

• An Addition Reaction is also known as both a Combination Reaction and a Synthesis Reaction.
• All three terms refer to a chemical reaction where two or more substances combine to form a new, single compound.

Explanation

• Sand does not dissolve in water.
• Unlike sugar, glucose, and salt, which are all soluble in water.

Explanation

DNA (Deoxyribonucleic acid) is a large molecule made up of smaller units called nucleotides. Each nucleotide is composed of:

• A sugar molecule (deoxyribose)
• A phosphate group
• One of four nitrogenous bases: Adenine (A), Guanine (G), Cytosine (C), and Thymine (T)

Explanation

• Chromosomes are thread-like structures made up of DNA and proteins that carry genetic information from one generation to the next.
• They are found in the nucleus of living cells and play a crucial role in inheritance and genetic diversity.

Explanation

Thermal energy can be transferred through all three methods:

• Conduction: Direct transfer between particles in physical contact.
• Convection: Transfer through the movement of fluids.
• Radiation: Transfer through electromagnetic waves (e.g., light, radio waves).