Explanation:
“The isomers butane and methyl propane have the same molecular formula and different properties”, this is because structural isomers usually have different properties to their parent.
Which of the following measurements is expressed to three significant figures?
C. 5.60 km
Hope this helps!
It simply equals 4x-16.......
the expression is in lowest terms, so you can’t do anything else
<u>Answer:</u> The volume of given amount of ethanol at this temperature is 159.44 mL
<u>Explanation:</u>
Specific gravity is given by the formula:
We are given:
Density of water = 0.997 g/mL
Specific gravity of ethanol = 0.787
Putting values in above equation, we get:
Density is defined as the ratio of mass and volume of a substance.
......(1)
Given values:
Mass of ethanol = 125 g
Density of ethanol = 0.784 g/mL
Putting values in equation 1, we get:
Hence, the volume of given amount of ethanol at this temperature is 159.44 mL
Methane is the compound CH4, and burning it uses the reaction:
CH4 + O2 -> CO2 + H2O, which is rather exothermic. To find the heat released by burning a certain amount of the substance, you should look at the bond enthalpy of each compound, and then compare the values before and after the reaction. In methane, there are 4 C-H bonds, which have bond energy of 416 kj/mol, resulting in a total bond energy of 1664 kj/mol. O2 is 494 kj/mol. Therefore we have a total of 2080 kj/mol on the left side. On the right side we have CO2, which has 2 C=O bonds, each at 799 kj/mol each, resulting in 1598 kj/mol, and H2O has 2 O-H bonds, at 459kj/mol each, resulting in a total of 2516 kj/mol on the right hand side. Now, this may be confusing because the left hand side seems to have less heat than the right, but you just need to remember: making minus breaking, which results in a total change of 436kj/mol heat evolved.
Now it is a simple matter of find the mols of CH4 reacted, using n=m/mr.
n = 9.5/16.042 = 0.592195 mol
Therefore, if we reacted 0.592195 mol, and we produced 436 kj for one mol, the total amount of energy evolved was 436*<span>0.592195 kj, or 258.197 kj.</span>
