Try to grow a plant with and without soil
<span>the elements in groups1a, 2a, 3a have positive charges according to their group numbers</span>
Essential amino acids
Amino acids are the molecules that make up proteins when they are linked up. There are certain essential amino acids, namely they are <span>histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
All of these must be obtained from one's diet. If they are not, the body will use existing proteins, such as muscle mass, to obtain them.</span>
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Answer:</h2>
Option B. Potassium(K).
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Explanation:</h2>
Electronic configuration of the given elements are:
- Ca - [Ar] 4s²
- K - [Ar] 4s¹
- B - [He] 2s2 2p1
- Kr - [Ar] 3d¹⁰4s²4p⁶
- Krypton(K) have 36 electrons and it is a noble gas and hence all of its shells are completely filled with electrons and hence it will never loose electrons in normal conditions.
- Boron(B) have 5 electrons and 3 electrons in its outer shell. In order to attain a stable configuration it will loose 3 electrons and it is difficult to loose 3 electrons at a time for an atom.
- Calcium(Ca) have 20 electrons and 2 electrons in its outermost shell, in order to attain a stable configuration it will loose 2 electrons. it is quite difficult but easier than Boron.
- Potassium(K) have 21 electrons and 1 electron in its outermost orbit and in order to attain a stable configuration it will loose 1 electron. It is much easier to donate 1 electron than 2 or 3 electrons.
Result: Potassium will loose an electron most easily from the given elements.
Answer:14.93
Explanation:heat gained=heat lost
120.5 ×4.184×change=7525
7525÷504.172
Ans14.925