Answer:
Alpha decay is a form of nuclear fission in which the parent atom splits into two daughter products. When an atomic nucleus releases an alpha particle, the atom decays (is transformed) into another atom with a mass number that is lower by 4 and an atomic number that is lower by 2.
Explanation:
Answer:
The high melting point is also consistent with its description as an ionic solid. In the crystal, each S2− ion is surrounded by an octahedron of six Ca2+ ions, and complementarity, each Ca2+ ion surrounded by six S2− ions.
Explanation:
You can use the periodic table to predict whether an atom will form an anion or a cation, and you can often predict the charge of the resulting ion. Atoms of many main-group metals lose enough electrons to leave them with the same number of electrons as an atom of the preceding noble gas. To illustrate, an atom of an alkali metal (group 1) loses one electron and forms a cation with a 1+ charge; an alkaline earth metal (group 2) loses two electrons and forms a cation with a 2+ charge, and so on. For example, a neutral calcium atom, with 20 protons and 20 electrons, readily loses two electrons. This results in a cation with 20 protons, 18 electrons, and a 2+ charge. It has the same number of electrons as atoms of the preceding noble gas, argon, and is symbolized Ca2+. The name of a metal ion is the same as the name of the metal atom from which it forms, so Ca2+ is called a calcium ion.
When atoms of nonmetal elements form ions, they generally gain enough electrons to give them the same number of electrons as an atom of the next noble gas in the periodic table. Atoms of group 17 gain one electron and form anions with a 1− charge; atoms of group 16 gain two electrons and form ions with a 2− charge, and so on. For example, the neutral bromine atom, with 35 protons and 35 electrons, can gain one electron to provide it with 36 electrons. This results in an anion with 35 protons, 36 electrons, and a 1− charge. It has the same number of electrons as atoms of the next noble gas, krypton, and is symbolized Br−. (A discussion of the theory supporting the favored status of noble gas electron numbers reflected in these predictive rules for ion formation is provided in a later chapter of this text.)
Answer:
Aluminium oxide has higher melting point than aluminium chloride because there nay be some impurities in the oxide which affects the intermolecular force of attraction
<u>Answer:</u> The correct answer is Option A.
<u>Explanation:</u>
Electronegativity is defined as the tendency of an atom to attract the shared pair of electrons towards itself whenever a bond is formed.
This property increases as we move from left to right across a period because the number of charge on the nucleus gets increased and electrons are attracted more towards the nucleus.
This property decreases as we move from top to bottom in a group because the electrons get add up in the new shells which make them further away from the nucleus.
Thus, the correct answer is Option A.
