Answer: 
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Explanation:
The order of boiling point depends upon the type of interactions present between the molecules.
Potassium fluoride (KF) is an ionic compound and the opposite ions are held together by strong electrostatic forces.
is a covalent compound and the molecules are held together by weak van der Waals' forces.
Formaldehyde is a polar compound due to presence of polar carbonyl group. Hence dipole-dipole force is present between formaldehyde molecules.
Thus the decreasing order of boiling point is:
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B. Solid water conforms to the shape of its container.
The Milliliters that occupy when its pressure is 755 mmhg is calculated using Bolyes law fomula
that is P1v1 = p2 V2
p1= 735mmhg
V1= 350 Ml
P2= 755 mm hg
V2= ?
from the formula above V2 is therefore= p1V1/P2
= 350 x735/755= 340.73 Ml
An Exothermic reaction releases energy into the surroundings and so the products have more potential energy then the reactants. The enthalpy change is a negative value. Whereas, an endothermic reaction involves the absorption of energy into the system and so the reactants have more potential energy than the products. The enthalpy change is a positive value. This is clearly represented in energy profile diagrams.
From the information give, I'm going to assume the wave is in a vacuum...
You use the equation: f=
where c is the constant for speed of light (
so f=
f= 4.89 x
Hz (approximately)
