The noble gas configuration system helps to shorten the total electron configuration by using the symbol for the noble gas that lies before the particular element in the periodic table.
For example:
Na has atomic number 11
Electron configuration of Na: 1s2 2s2 2p6 3s1
Noble gas electron configuration of Na: [Ne] 3s1
Ne has atomic number 10 and lies before Na in the periodic table.
Answer:
0.01395mol Cr2O3
Explanation:
the molar mass of Cr2O3 is 151.9904 g/mol
2.12g Cr2O3 x 1 mol/151.9904g = 0.01395mol Cr2O3
The heat is the required energy.
Answer:
n = 3.0 moles
V = 60.0 L
T = 400 K
From PV = nRT, you can find P
P = nRT/V = (3.0 mol)(0.0821 L-atm/K-mol)(400 K)/60.0L
P = 1.642 atm = 1.6 atm (to 2 significant figures)
Explanation:
I'm not positive what evaporations you need but I have these.....
1. Wind assists evaporation; for example in clothes dry faster under a fan.
2. Heat assists evaporation; for example, in summer clothes dry faster than in winter.
3. Increase in surface area exposed assists evaporation; for instance, a wet cloth spread out dries faster than when folded.
4. Dryness assists evaporation; for instance, clothes dry faster in summer than during the monsoon when the air is humid.
5. The rate of evaporation depends upon the nature of the liquid; for example, petrol evaporates faster than water.
6. Vapor pressure: if pressure is applied on the surface of a liquid, evaporation is hindered; consider, for example, the case of a pressure cooker.
