Explanation

Biomass energy comes from plants, which get their energy through photosynthesis using sunlight.

So, the Sun is the original source of energy for all biomass.

Explanation

Osmosis is the movement of water molecules through a semipermeable membrane from an area of higher water concentration to lower concentration.

It is a vital process in biological systems for maintaining cell balance.

Explanation

Given:

Volume of compound C at STP = 0.112 dm³

1 mole gas at STP = 22.4 dm³

So, moles of C = 0.112 ÷ 22.4 = 0.005 mol

CO₂ produced:

Mass = 0.88 g

Moles of CO₂ = 0.88 ÷ 44 = 0.02 mol

Mole ratio:

0.005 mol of C → produced 0.02 mol of CO₂

Ratio CO₂ : C = 0.02 ÷ 0.005 = 4

👉 That means 4 carbon atoms are present in one molecule of C.

Explanation

An electric field is the region around a charged particle where it exerts a force on other charges.

It is represented by field lines.

It is measured in newtons per coulomb (N/C).

Explanation

• Oxygen has 8 protons and typically 8 neutrons, giving it a mass number of 16.
• Mass number = Number of protons + Number of neutrons.
• Discoverers: Joseph Priestley, Carl Wilhelm Scheele
• Symbol: O
• Atomic number: 8
• Electrons per shell: 2, 6
• Discovered: 1774

Explanation

As altitude increases, pressure decreases because there is less air above, resulting in less weight pressing down.

This causes the air to become less dense and "thinner," meaning there are fewer air molecules in a given volume. 

Pressure measures force per unit area, with SI units of pascals (1 pascal = 1 newton per square metre, 1 N/m2).

Explanation

• Water covers approximately 71% of the Earth's surface.

Additional information

• Land Coverage: The remaining 29% of the Earth's surface consists of land, including continents and islands.
• Water Distribution: About 96.5% of Earth's water is held in the global oceans as saltwater

Explanation

Explanation

An electric circuit is a closed path through which electric current flows.

It enabling the transfer of electrical energy.

Electric current is measured in amperes using an ammeter.

Explanation

In endothermic reactions, energy in the form of heat is taken in from the surroundings.

Examples include photosynthesis and melting of ice, where heat is absorbed to proceed.

In an exothermic reaction, energy (heat) is released/evolved to the surroundings.

Examples include combustion of fuels and respiration.