Answer:
On the Moh's scale of hardness, aluminum oxide is positioned just below to diamond due to which it is considered as one of the hardest known compounds. This also shows that the compound exhibit an enormous amount of lattice energy, as to transform the oxide into its constituent ions, the energy is required to overcome.
Based on the chemical formula of the compound, that is, Al2O3, it is shown that the ions of Al3+ and O2- are kept close due to the activity of the strong electrostatic ionic bonds. The electrostatic forces and the ionic bonding between the ions are extremely robust due to the presence of the ions high charge density. Therefore, to dissociate the bonds, an enormous amount of energy is needed, and at the same time, a high amount of lattice energy is present.
Answer:
Molar mass = 94972.745 g/mol
Explanation:
Given data:
Density = 2.25 g/ml
Pressure = 700 mmHg
Temperature = 200°C
Molar mass = ?
Solution:
Density = 2.25 g/ml (2.25×1000 = 2250 g/L)
Pressure = 700 mmHg (700/760 = 0.92 atm)
Temperature = 200°C (200+273 = 473K)
Formula:
d = PM/RT
M = dRT/P
M = 2250 g/L × 0.0821 atm.L /mol.K × 473K / 0.92 atm
M = 87374.93 g/mol / 0.92
M = 94972.745 g/mol
<span>A. Commercial cooking
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Answer:
five half lives
Explanation:
Half-life is the time required for a quantity to reduce to half of its initial value.
How many half lives it would take to reach 3.13% form 100% of it's initial concentration:
100% - 50% : First Half life
50% - 25%: Second Half life
25% - 12.5%: Third Half life
12.5% - 6.25%: Fourth Half life
6.25% - 3.125%: Fifth Half life
This means it would take five half lives to get to 3.125% (≈ 3.13%) of it's original concentration.
Answer: The partial pressure of oxygen in the mixture if the total pressure is 525 mmHg is 310 mm Hg
Explanation:
mass of nitrogen = 37.8 g
mass of oxygen = (100-37.8) g = 62.2 g
Using the equation given by Raoult's law, we get:
= partial pressure of 
= ?
= total pressure of mixture = 525 mmHg
Total moles = 1.94 + 1.35 = 3.29 moles
Thus the partial pressure of oxygen in the mixture if the total pressure is 525 mmHg is 310 mm Hg
