Melting points and boiling points of molecular compound are usually lower than ionic compounds. This is so as only a small amount of energy is required to overcome the weak intermolecular forces of attraction (Van de Waals forces) thus having lower m.p. and b.p.
Ionic compounds require a large amount of energy to overcome the strong electrostatic forces of attraction between the ions, hence having higher mp and bp
Answer:
There are no changes in primary atmospheric gases even if height is 18,000 ft.
It feels like oxygen is low at such heights but it is not. At height of 18000 ft oxygen will be same in air (21%) but due to decrease in pressure it will be difficult to breathe.
Explanation:
As we move to higher altitudes, the pressure reduces if we compare it with sea level but the important thing to note is composition of air remains the same which is 78% Nitrogen, 21% oxygen and 1% other gases (including Carbon dioxide). There are no changes in primary atmospheric gases even if height is 18,000 ft but the problem which can be faced is breathing because pressure is low at such height and it will be difficult for lungs to take oxygen in.
It feels like oxygen is low at such height but it is not. At height of 18000 oxygen will be same in air(21%) but due to decrease in pressure it will be difficult to breathe.
Answer:
The answer to your question is below
Explanation:
See the attachment.
Synthesis ΔH
ΔH = 25 - (-30) = 25 + 30 = 55 kJ Endothermic reaction
Single reaction
ΔH = 30 - 65 = -35 KJ Exothermic reaction
Double reaction
ΔH = 60 - 10 = 50 kJ Endothermic reaction