SCIENCE
PHYSICAL SCIENCES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Na & Cl
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Ca & Sr
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Ca & Br
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O & C
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Detailed explanation-1: -Ca and Ba are earth-alcaline metals and have similiar characteristics: are solid rather reactive with a basic features in water.
Detailed explanation-2: -Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium.
Detailed explanation-3: -Elements in the same column of the Periodic Table have similar chemical properties.
Detailed explanation-4: -Group 2A (or IIA) of the periodic table are the alkaline earth metals: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).
Detailed explanation-5: -Calcium is a silvery-white, soft metal that tarnishes rapidly in air and reacts with water. Calcium metal is used as a reducing agent in preparing other metals such as thorium and uranium. It is also used as an alloying agent for aluminium, beryllium, copper, lead and magnesium alloys.