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:
The materials are opaque or crystalline from a client to the orientation and type of union between their atoms, forming two types of structures.
These two structures can be crystalline or amorphous.
In the case of being crystalline, these unions do not allow light to pass through the medium of the object or body of said compound, making it totally refract and giving the appearance of OPAQUE.
On the other hand, in those compounds that we call amorphous, the atoms are located in a different way that makes light pass through them, without absorbing or identifying any light beam, so they look transparent.
Explanation:
Example: A glass cup has an amorphous structure, while a porcelain or porcelain plate has a crystalline structure.
He could be blindfolded and know which was his and which was his sister's. All he would need to do is pick them both up and if they were too big then pick them up one at a time. The lumber might make it harder to tell, but this is a question about physical properties.
So there is a change in mass which for the purpose of this question should be quite different. His sister's ought to be much lighter than his. He would find it easier to pick up.
Part (a) :
H₂(g) + I₂(s) → 2 HI(g)
From given table:
G HI = + 1.3 kJ/mol
G H₂ = 0
G I₂ = 0
ΔG = G(products) - G(reactants) = 2 (1.3) = 2.6 kJ/mol
Part (b):
MnO₂(s) + 2 CO(g) → Mn(s) + 2 CO₂(g)
G MnO₂ = - 465.2
G CO = -137.16
G CO₂ = - 394.39
G Mn = 0
ΔG = G(products) - G(reactants) = (1(0) + 2*-394.39) - (-465.2 + 2*-137.16) = - 49.3 kJ/mol
Part (c):
NH₄Cl(s) → NH₃(g) + HCl(g)
ΔG = ΔH - T ΔS
ΔG = (H(products) - H(reactants)) - 298 * (S(products) - S(reactants))
= (-92.31 - 45.94) - (-314.4) - (298 k) * (192.3 + 186.8 - 94.6) J/K
= 176.15 kJ - 84.78 kJ = 91.38 kJ
When the charged balloon is brought near the wall, it repels some of the negatively charged electrons in that part of the wall. Therefore, that part of the wall is left repelled.
<u>Explanation</u>:
- Balloons don't stick to walls. However, if you rub the balloon on an appropriate piece of material such as clothing or a wall, electrons are pulled from the other material to the balloon.
- The balloon now as more electrons than normal and therefore has an overall negative charge. Two balloons like this will repel each other.
- The other material now has an overall positive charge. Because opposite charges attract, the balloon will now appear to stick to the other material. If you didn't rub the balloon first, it's charge would be neutral and it wouldn't stick to the wall.
