Explanation

• Chlorophyll is a compound that is called a Chelate. 

  Photosynthesis depends on the presence of chlorophyll for the absorption of light.

  There are about five closely related chlorophylls:

  1. chlorophyll a
  2. chlorophyll b
  3. chlorophyll c
  4. chlorophyll d
  5. chlorophyll e
  6. chlorophyll f

Explanation

• Photovoltaic (PV) cells convert solar energy into electricity through a physical and chemical phenomenon known as the photovoltaic effect.
• Photovoltaic cells are also called solar cells.
• They convert light energy from the Sun directly into electrical energy.

Explanation

Sound travels at approximately 1,100 feet per second (766 miles per hour).

Radio waves travel at the speed of light, which is approximately 186,000 miles per second.

Explanation

Angina pectoris is the medical term for chest pain or discomfort due to coronary heart disease.

It occurs when the heart muscle doesn't get as much blood as it needs.

This usually happens because one or more of the heart's arteries is narrowed or blocked, also called ischemia

Explanation

 Titanium element has an atomic number of 22 and a mass of 47.90

Explanation

The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium.

Explanation

Magnetic effect.

Chemical effect.

Heating effect.

Electric shocks.

Explanation

The solar system is a system constrained by the gravity of the sun and the objects that orbit it. The solar system was formed 4.6 billion years ago by the gravitational collapse of a huge interstellar molecule cloud.

Explanation

C

A total solar eclipse occurs when the Moon is exactly positioned between the Sun and the Earth and the Earth passes through the Moon's shadow. Solar eclipses can only happen during the day and at the time of a new Moon. Total solar eclipses last for only a few minutes.

while on the other hand 

During a lunar eclipse, Earth comes between the Sun and the Moon, blocking the sunlight falling on the Moon. There are two kinds of lunar eclipses: A total lunar eclipse occurs when the Moon and Sun are on opposite sides of Earth.

Explanation

Mendeleev is best known for discovering periodic law in 1869.