<span>A)How many moles of O2 are required for the complete combustion of 2.2 g of C3H8 to form CO2 and H2O?
C3H8 + 5O2 = 3CO2 + 4H2O
2.2 g C3H8 ( 1 mol / 44.11 mol ) ( 5 mol O2 / 1 mol C3H8) = 0.25 mol O2
b)A 65.25 g sample of CuSO4•5H2O (M = 249.7) is dissolved in enough water to make 0.800 L of solution. What volume of this solution must be diluted with water to make 1.00 L of 0.100 M CuSO4?
M1V1 = M2V2
[65.25 ( 1 / 249.7 )/ 0.800 L] (V1)= 0.100 (1.00 L)
V1 = 0.31 L or 310 mL </span>
The solution of Ba(OH)2 will have the lowest freezing point. This is because it dissociates into 3 ions, one Ba and 2 OH, which is more than any of the others. Freezing point depression is a colligitive property of water that depends, in part, on the number of ions.
hope it helps
Answer:
Benzaldehyde is less electrophilic than acetaldehyde
Explanation:
Electrophilicity of carbonyl carbon depends on it's positive charge density.
In benzaldehyde, phenyl group can act as an electron donating group towards carbonyl group due to it's electron donating resonating effect.
In acetaldehyde, methyl group can act as an electron donating group towards carbonyl group due to it's electron donating inductive effect.
We know that resonating effect are more stronger than inductive effect.
Henece, it is expected that positive charge density on carbonyl carbon is much lower in benzaldehyde than acetaldehyde.
So, benzaldehyde is less electrophilic than acetaldehyde.
Resonating effect of phenyl group has been shown below.
The end of the world as we know it could come in any number of ways, depending on who you ask. Some people believe global cataclysm will occur when Earth's magnetic poles reverse. When north goes south, they say, the continents will lurch in one direction or the other, triggering massive earthquakes, rapid climate change and species extinctions.
The most dramatic changes that occur when the poles reverse is a very large decrease of the total field intensity,
Earth's magnetic field takes between 1,000 and 10,000 years to reverse, and in the process, it greatly diminishes before it re-aligns. It's not a sudden flip, but a slow process, during which the field strength becomes weak, very probably the field becomes more complex and might show more than two poles for a while, and then builds up in strength and [aligns] in the opposite direction.
Answer:
<u><em>Pangaea</em></u>
<u><em>Alfred Wegner</em></u>
<u><em>plate tectonics</em></u>
Explanation:
What did Earth look like 250 million years ago? The continents of Earth were clustered together in formation that a scientist named<em> </em><u>Pangaea</u><u><em>.</em></u>The scientist that named "Pangaea" was a German scientist by the name of <u>Alfred Wegner.</u> He theorized that "Pangaea" split apart and the different landmasses, or continents, drifted to their current locations on the globe. Wegener's theories of plate movement became the basis for the development of the theory of <u>plate tectonics.</u>