Answer:
Hydrogen
Explanation:
It is considered a special element due to its flexibility in giving up & taking in electrons, therefore making it good for organic & inorganic chemistry. Hydrogen has only one proton and one electron and is the only element which has no neutrons. it is considered as the simplest element in the universe and gives a valid reason for it to be the most abundant and common element in the universe.
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The reaction is given by

Barium goes underneath beta decay to form Ceaseum
- Cs is very mellable element
- It can melt on your hand
Unsaturated organic compounds with a carbon-to-carbon double bond and alkynes with a carbon-to-carbon triple bond, as well as aldehydes and ketones with a carbon-to-oxygen double bond, undergo addition reactions.
Answer:
The answer to your question is D. 25 grams.