What is the shielding effect and what is the screening effect

What is the molar mass of calcium?

The chemical symbol of calcium element  – Ca

Atomic number – 20

Electronic configuration – 1s²2s²2p⁶3s²3p⁶4s²

Molar mass of the calcium is – 40.078 u

The occurrence of calcium:

Calcium is an alkaline mineral found on the surface of the Earth. Bones, teeth, shells, rocks, and minerals all contain it. Limestone, marble, and chalk are all made up of calcium carbonate, which is a naturally occurring substance. Calcium carbonate precipitates out of solution to produce stalagmites and stalactites in caves.

Properties of calcium:

• Calcium is a soft metal with a gleaming silver surface.
• Calcium combines with oxygen to form a coating of white or gray calcium oxide, which soon dulls the surface.
•  Calcium has a melting temperature of 850 degrees Celsius (1,560 degrees Fahrenheit) and a boiling point of 1,440 degrees Celsius (2,620 degrees Fahrenheit).
• In the planet’s crust, it is the seventh most plentiful metal (4.1 percent ).
• Gypsum (calcium sulfate), limestone (calcium carbonate), apatite (calcium chloro- or fluoro-phosphate), and fluorite (calcium chloro- or fluoro-phosphate) are all found in great numbers (calcium fluoride).
• Hard water contains dissolved calcium bicarbonate.

Uses of calcium:

• Other metals, such as thorium and uranium, are prepared using calcium metal as a reducing agent.
• Aluminum, beryllium, copper, lead, and magnesium alloys all use it as an alloying agent.
• Calcium compounds are widely employed in a variety of applications. There are enormous reserves of limestone (calcium carbonate), which are employed both directly and indirectly in the construction of buildings. When limestone is fired in kilns, carbon dioxide gas is released, leaving quicklime behind (calcium oxide).
• Slaked lime is formed when this reacts aggressively with water (calcium hydroxide). In the chemical industry, slaked lime is used to create cement, as a soil conditioner, and in water treatment to lower acidity. It’s also used to eliminate impurities from molten iron ore in the steelmaking process.