Allotropes are elements on the periodic table that have more than one crystalline form . There are three forms of the element carbon : Diamond, Graphite, and Fullerenes. Isotopes are atoms of the same element with the same atomic number but have a different mass number.
The third reason helped Rutherford to discover the nucleus.
Monoprotic acid are acids having
only one hydrogen atoms after dissociation into ions from its compound. The
monoprotic acid from among the following is HCl. The answer is letter D. HCl →
H+ + Cl-. Note that there is only one H+ ion upon dissociation.
Answer:
The first and last choice
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