Water's high heat capacity<span> is a property caused by hydrogen bonding among </span>water<span> molecules. When </span>heat<span> is absorbed, hydrogen bonds are broken and </span>water <span>molecules </span>can<span> move freely. When the temperature of </span>water decreases, the hydrogen bonds are formed and release a considerable amount of energy.
<span>Water's heat of vaporization is around 540 cal/g at </span>100 °C<span>, water's boiling point.
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Answer:
Evaporation occurs because among the molecules near the surface of the liquid there are always some with enough heat energy to overcome the cohesion of their neighbors and escape. At higher temperatures the number of energetic molecules is greater, and evaporation is more rapid.
The methane molecule undergoes oxidation and the carbon is oxidized to carbon dioxide and hydrogen to water.
In this reaction there is cleavage of four C-H bonds and two O=O bonds
there will be formation of two C=O bonds and four O-H bonds.
Overall due to more bond cleavage energy there will be evolution of energy. thus combustion is an exothermic reaction.
Answer is: (4) emits energy as it moves to a lower energy state.
Atom emits a characteristic set of discrete wavelengths, according to its electronic energy levels.
Emission spectrum of a chemical element is the spectrum of frequencies emitted due to an atom making a transition from a high energy state to a lower energy state.
Each transition has a specific energy difference.
Each element's emission spectrum is unique.
Answer:
9.36
Explanation:
Sodium formate is the conjugate base of formic acid.
Also,
for sodium formate is 
Given that:
of formic acid = 
And, 
So,
Concentration = 0.35 M
HCOONa ⇒ Na⁺ + HCOO⁻
Consider the ICE take for the formate ion as:
HCOO⁻ + H₂O ⇄ HCOOH + OH⁻
At t=0 0.35 - -
At t =equilibrium (0.35-x) x x
The expression for dissociation constant of sodium formate is:
![K_{b}=\frac {[OH^-][HCOOH]}{[HCOO^-]}](https://tex.z-dn.net/?f=K_%7Bb%7D%3D%5Cfrac%20%7B%5BOH%5E-%5D%5BHCOOH%5D%7D%7B%5BHCOO%5E-%5D%7D)
Solving for x, we get:
x = 0.44×10⁻⁵ M
pOH = -log[OH⁻] = -log(0.44×10⁻⁵) = 4.64
pH + pOH = 14
So,
<u>pH = 14 - 4.64 = 9.36</u>
