Answer:
B) Native fish species will begin to decrease in population size.
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The element having valency of 1 is ~
Answer:
(a) (i) All the elements of a group have similar chemical properties because they have same no. of valence electrons in their outermost shell. (ii) All the elements of a period have different chemical properties because they have different no. of valence electrons in their atoms.
Rutherford's Gold Foil Experiment proved the existence of a small massive center to atoms, which would later be known as the nucleus of an atom. Ernest Rutherford, Hans Geiger and Ernest Marsden carried out their Gold Foil Experiment to observe the effect of alpha particles on matter.