Answer:
The molarity of the sulfuric acid is 0.018 M
Explanation:
The molarity of a solution is the number of moles of the solute (sulfuric acid in this case) in a 1-liter solution.
Every 100 g of the solution, we have 95 g sulfuric acid because its concentration is 95% w/w.
With the density, we can calculate how many liters are 100 g of solution:
density = mass / volume
1.85 g / ml = 100 g / volume
volume = 100 g / 1.85 g/ml
volume = 54.1 ml or 0.0541 l
Now, we know that we have 95 g sulfuric acid in 0.0541 l solution. In 1 l, we have then:
1 l * 95g / 0.0541 l = 1.756 g sulfuric acid.
But we want to know how many moles sulfuric acid we have per liter. Then, using the molar mass, we can calculate how many moles there are in 1.756 g sulfuric acid:
1.756 g * 1 mol / 98.08 g = 0.018 mol
The molarity is 0.018 M
<u>Answer:</u> The amount of energy released per gram of
is -71.92 kJ
<u>Explanation:</u>
For the given chemical reaction:

The equation used to calculate enthalpy change is of a reaction is:
![\Delta H^o_{rxn}=\sum [n\times \Delta H^o_f_{(product)}]-\sum [n\times \Delta H^o_f_{(reactant)}]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28product%29%7D%5D-%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28reactant%29%7D%5D)
The equation for the enthalpy change of the above reaction is:
![\Delta H^o_{rxn}=[(5\times \Delta H^o_f_{(B_2O_3(s))})+(9\times \Delta H^o_f_{(H_2O(l))})]-[(2\times \Delta H^o_f_{(B_5H_9(l))})+(12\times \Delta H^o_f_{(O_2(g))})]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%285%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28B_2O_3%28s%29%29%7D%29%2B%289%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28H_2O%28l%29%29%7D%29%5D-%5B%282%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28B_5H_9%28l%29%29%7D%29%2B%2812%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28O_2%28g%29%29%7D%29%5D)
Taking the standard enthalpy of formation:

Putting values in above equation, we get:
![\Delta H^o_{rxn}=[(5\times (1271.94))+(9\times (-285.83))]-[(2\times (73.2))+(12\times (0))]\\\\\Delta H^o_{rxn}=-9078.57kJ](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%285%5Ctimes%20%281271.94%29%29%2B%289%5Ctimes%20%28-285.83%29%29%5D-%5B%282%5Ctimes%20%2873.2%29%29%2B%2812%5Ctimes%20%280%29%29%5D%5C%5C%5C%5C%5CDelta%20H%5Eo_%7Brxn%7D%3D-9078.57kJ)
We know that:
Molar mass of pentaborane -9 = 63.12 g/mol
By Stoichiometry of the reaction:
If 2 moles of
produces -9078.57 kJ of energy.
Or,
If
of
produces -9078.57 kJ of energy
Then, 1 gram of
will produce =
of energy.
Hence, the amount of energy released per gram of
is -71.92 kJ
the answer is fresh water
In scientific notation, a number is less than ten but more than one.
Move the decimal point from 0, 250.000 <- this is the same as 250 to between 2 and 5.
I had to move two spaces.
2.5^2
I hope this helps!
~kaikers
The genetic combination of two alles