Answer:
ΔS> 0 means Letter A
Explanation:
Processes that involve an increase in entropy of the system (ΔS > 0) are very often spontaneous; however, examples to the contrary are plentiful. By expanding consideration of entropy changes to include the surroundings, we may reach a significant conclusion regarding the relation between this property and spontaneity. In thermodynamic models, the system and surroundings comprise everything, that is, the universe, and so the following is true:
\displaystyle \Delta {S}_{\text{univ}}=\Delta {S}_{\text{sys}}+\Delta {S}_{\text{surr}}
Answer:
- <u>You need to convert the number of atoms of Ca into mass in grams, using Avogadro's number and the atomic mass of Ca.</u>
Explanation:
The amount of matter is measured in grams. Thus, you need to convert the number of atoms of Ca (calcium) into mass to compare with 2.45 grams of Mg.
To convert the atoms of calcium into mass, you divide by Avogadro's number, to obtain the number of moles of atoms, and then divide by the atomic mass of calcium.
<u />
<u>1. Number of moles, n</u>

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<u>2. Mass</u>
- mass = number of moles × atomic mass
- mass = 0.053969mol × 40.078g/mol = 2.16g
Then, 2.45 g of Mg represent a greaer mass than the 3.25 × 10²² atoms of Ca.
Answer:
- Initial: forward rate > reverse rate
- Equilibrium: forward rate = reverse rate
Explanation:
2NO₂(g) → N₂O₄(g) Kc=4.7
The definition of <em>equilibrium</em> is when the forward rate and the reverse rate are <em>equal</em>.
Because in the initial state there's only NO₂, there's no possibility for the reverse reaction (from N₂O₄ to NO₂). Thus the forward rate will be larger than the reverse rate.
After 100years, sample is 250g
After 200 years, sample is 125g
After 300years, sample is 62.5 g
Answer:
A
Explanation:
increase in energy - hotter and/or more reactive
decrease in energy - colder and/or less reactive
Since it is going from a liquid to solid it will have a tighter arrangement of particles.