An ionic compound is a chemical compound of ions held together by electrostatic forces termed ionic bonding
EXAMPLE -/Sodium chloride ,NaCl with Na+and Ci- ions
<h2>Answer:</h2>
<u>Temperature dependency is responsible for the process that hot water freeze faster than cold water.</u>
<h2>Explanation:</h2>
The effect given above is called Mpemba Effect. According to this idea hot water freezes more quickly as compared to cold water. But until now there is no convincing explanation for this strange phenomenon. One idea is that hot containers make better thermal contact with a refrigerator and so conduct heat more efficiently because a good conductor is good fro the transfer of heat. Another idea about this effect is that warm water evaporates more quickly and since this is an endothermic process, it cools the water making it freeze more quickly.
B. White Dwarf.
<h3>Explanation</h3>
The star would eventually run out of hydrogen fuel in the core. The core would shrink and heats up. As the temperature in the core increases, some of the helium in the core will undergo the triple-alpha process to produce elements such as Be, C, and O. The triple-alpha process will heat the outer layers of the star and blow them away from the core. This process will take a long time. Meanwhile, a planetary nebula will form.
As the outer layers of gas leave the core and cool down, they become no longer visible. The only thing left is the core of the star. Consider the Chandrasekhar Limit:
Chandrasekhar Limit: 
.
A star with core mass smaller than the Chandrasekhar Limit will not overcome electron degeneracy and end up as a white dwarf. Most of the outer layer of the star in question here will be blown away already. The core mass of this star will be only a fraction of its 
, which is much smaller than the Chandrasekhar Limit.
As the star completes the triple alpha process, its core continues to get smaller. Eventually, atoms will get so close that electrons from two nearby atoms will almost run into each other. By Pauli Exclusion Principle, that's not going to happen. Electron degeneracy will exert a strong outward force on the core. It would balance the inward gravitational pull and prevent the star from collapsing any further. The star will not go any smaller. Still, it will gain in temperature and glow on the blue end of the spectrum. It will end up as a white dwarf.
Answer:
T° freezing solution → -11.3°C
T° boiling solution → 103.1 °C
Explanation:
Assuming 100 % dissociation, we must find the i, Van't Hoff factor which means "the ions that are dissolved in solution"
This salt dissociates as this:
SnCl₄ (aq) → 1Sn⁴⁺ (aq) + 4Cl⁻ (aq) (so i =5)
The formula for the colligative property of freezing point depression and boiling point elevation are:
ΔT = Kf . m . i
where ΔT = T° freezing pure solvent - T° freezing solution
ΔT = Kb . m . i
where ΔT = T° boiling solution - T° boiling pure solvent
Freezing point depression:
0° - T° freezing solution = 1.86°C/m . 1.22 m . 5
T° freezing solution = - (1.86°C/m . 1.22 m . 5) → -11.3°C
Boiling point elevation:
T° boiling solution - 100°C = 0.512 °C/m . 1.22 m . 5
T° boiling solution = (0.512 °C/m . 1.22 m . 5) + 100°C → 103.1 °C
Answer:
• The Na atom is formed when the Na+ ion gains an electron.
• A Na+ ion has 10 electrons and a Na atom has 11 electrons.
• A sodium atom has one more electron shell than a sodium ion.
• A Na+ ion is formed when a Na atom loses an electron
