Answer:
M Na2SO4 sln = 0.8448 M
Explanation:
∴ mass Na2SO4 = 3.00 g
∴ volume soln = 25 mL = 0.025 L
∴ molar mass Na2SO4 = 142.04 g/mol
⇒ mol Na2SO4 = (3.00 g)*(mol/142.04 g) = 0.02112 mol
⇒ M Na2SO4 sln = (0.02112 mol/0.025 L ) = 0.8448 M
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>
Answer:
Bin 1 points to a carbon bonded to a double bonded carbon and single bonded to two hydrogens. --- trigonal planar, tetrahedral
Bin 2 points to a carbon double bonded to a carbon and single bonded to a carbon and one hydrogen.------- trigonal planar, tetrahedral
Bin 3 is a carbon single bonded to two carbons and single bonded to two hydrogens. ----- tetrahedral, tetrahedral
Bin 4 is the same as bin 3.--------tetrahedral, tetrahedral
Bin 5 is a carbon triple bonded to a carbon and single bonded to a carbon.---- linear, tetrahedral
Bin 6 is triple bonded to a carbon and single bonded to a hydrogen.---linear, tetrahedral
Explanation:
A single C-C or C-H bond is in a tetrahedral geometry, the carbon atom is bonded to four species with a bond angle of 109°.
A C=C bond is trigonal planar with a bond angle of 120°.
Lastly, a C≡C bond has a linear geometry with a bond angle of 180° between the atoms of the bond.
Answer:
A = 1,13x10¹⁰
Ea = 16,7 kJ/mol
Explanation:
Using Arrhenius law:
ln k = -Ea/R × 1/T + ln(A)
You can graph ln rate constant in x vs 1/T in y to obtain slope: -Ea/R and intercept is ln(A).
Using the values you will obtain:
y = -2006,9 x +23,147
As R = 8,314472x10⁻³ kJ/molK:
-Ea/8,314472x10⁻³ kJ/molK = -2006,9 K⁻¹
<em>Ea = 16,7 kJ/mol</em>
Pre-exponential factor is:
ln A = 23,147
A = e^23,147
<em>A = 1,13x10¹⁰</em>
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I hope it helps!
