What exactly is the question you are asking?
Answer:
D
Explanation:
Since [pKa = - log Ka]....hence..,the larger the Ka value,the stronger the acid is..so this means that the pKa is vice versa
Saying that the smaller the pKa value..the stronger the acid is.
Answer:
Three hydrogen atoms to form PH₃.
Explanation:
Hello!
In this case, since the elements belonging to the nitrogen family (N, P, As, Sb and Bi) show five valence electrons, because there are five electrons at their outer shell, it is clear that if phosphorous bonds with hydrogen, it is going to require the same amount of oxygen atoms (3) because elements having five valence electrons need 3 bonds in order to attain the octet (5+3=8).
Therefore the compound would be:

Which is phosphine.
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Solar flare: a brief eruption of intense high-energy radiation from the sun's surface, associated with sunspots and causing electromagnetic disturbances on the earth, as with radio frequency communications and power line transmissions.
Sunspot Prominence: It is a large, bright, gaseous feature extending outward from the Sun's surface, often in a loop shape. It is similar to a Solar Flare
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