Answer:
proposing a hypothesis.
Explanation: Therefore the last step in the scientific method is proposing a hypothesis or obtaining a conclusion.
The noble gases are relatively unreactive because they have a stable octet of valence electrons.
Thus, they do not tend to undergo reactions in which they will gain or lose valence electrons,
However, <em>only He, Ne, and Ar are inert</em>. Kr and Xe combine with other highly reactive elements to form stable compounds.
D) life on earth was seeded by extraterrestrial aliens
Answer:
5. Atoms with high ionization energies and high electron affinities have low electronegativities.
Explanation:
Ionization energy is the minimum amount of energy which is required to knock out the loosely bound valence electron from the isolated gaseous atom.
Electron affinity is the amount of energy released when an isolated gaseous atom accepts electron to form the corresponding anion.
Electronegativity is the tendency of an atom in a bond pair to attract the shared pair of electron towards itself.
Low ionization energies as well as low electron affinities mean the atom has low effective nuclear charge, which results in the less attraction of the valence electrons by the atom and thus, low electronegativity.
Answer:
b. reactants are two ionic compounds.
Explanation:
A double-replacement reaction is different from a single-replacement reaction because a double-replacement reaction is a reaction between two ionic compounds while in a single-replacement reaction one atom replace another atom. In addition, the product formed from a double-replacement reaction often precipitate from the given solution.
