Answer:
V = 22.34 L
Explanation:
Given data:
Volume of O₂ needed = ?
Temperature and pressure = standard
Number of molecules of water produced = 6.0× 10²³
Solution:
Chemical equation:
2H₂ + O₂ → 2H₂O
Number of moles of water:
1 mole contain 6.022× 10²³ molecules
6.0× 10²³ molecules × 1 mole / 6.022× 10²³ molecules
0.99 mole
Now we will compare the moles of oxygen and water.
H₂O : O₂
2 : 1
0.996 : 0.996
Volume of oxygen needed:
PV = nRT
V = nRT/P
V = 0.996 mol × 0.0821 atm.L/mol.K × 273.15 K / 1 atm
V = 22.34 L
Answer:
D. Time and pressure changes dead plant material to peat.
Explanation:
There are four steps in the production of coal: peat, lignite, bituminous and anthracite.
Peat: in this stage dead plants are oxidized to water and carbon dioxide and buried under sediments. The partial decomposition of plant matter due to the absence of oxygen is called peat. There is no factor of time and pressure that changes dead plant material to peat.
Lignite: Peat is subjected to heat, pressure, and time to form lignite.
Bituminous: More pressure in lignite removes all the traces of plant matter and form “soft coal”, bituminous coal.
Anthracite: It is the last stage, in which hard coal forms with the combined pressure and high temperature.
Hence, the correct answer is "D. Time and pressure changes dead plant material to peat."
The best answer for this question is weak intermolecular forces. Volatility is used to call the tendency of substances to evaporate. A substance that has low volatility means that it easily evaporates and has a relatively low boiling point. When the intermolecular forces in the substance are weak, that means it is easier to separate them, making them more volatile.
