Answer:
pH = 9.25
Explanation:
Reaction of ammonia (NH₃) with hydrochloric acid (HCl) is:
NH₃ + HCl → NH₄⁺ + Cl⁻
As equal volumes of a 0.020M solution of NH₃ and a 0.010M solution of react, molarity of NH₃ after reaction is 0.010M and 0.010M of NH₄⁺.
For the buffer NH₄⁺/NH₃ H-H equation to find pH of solution is:
pH = pKa + log₁₀ [NH₃] / [NH₄⁺]
pH = 9.25 + log₁₀ [0.010M] / [0.010M]
<em>pH = 9.25</em>
You remove waste as a gas (carbon dioxide), as a liquid (urine and sweat), and as a solid. Excretion is the process of removing wastes and excess water from the body.
Answer:
The maximum amount of work that can be done by this system is -2.71 kJ/mol
Explanation:
Maximum amount of work denoted change in gibbs free energy
during the reaction.
Equilibrium concentration of B = 0.357 M
So equilibrium concentration of A = (1-0.357) M = 0.643 M
So equilibrium constant at 253 K, ![K_{eq}= \frac{[B]}{[A]}](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%20%5Cfrac%7B%5BB%5D%7D%7B%5BA%5D%7D)
[A] and [B] represent equilibrium concentrations
![K_{eq}=\frac{0.357}{0.643}=0.555](https://tex.z-dn.net/?f=K_%7Beq%7D%3D%5Cfrac%7B0.357%7D%7B0.643%7D%3D0.555)
When concentration of A = 0.867 M then B = (1-0.867) M = 0.133 M
So reaction quotient at this situation, ![Q=\frac{0.133}{0.867}=0.153](https://tex.z-dn.net/?f=Q%3D%5Cfrac%7B0.133%7D%7B0.867%7D%3D0.153)
We know, ![\Delta G=RTln(\frac{Q}{K_{eq}})](https://tex.z-dn.net/?f=%5CDelta%20G%3DRTln%28%5Cfrac%7BQ%7D%7BK_%7Beq%7D%7D%29)
where R is gas constant and T is temperature in kelvin
Here R is 8.314 J/(mol.K), T is 253 K, Q is 0.153 and
is 0.555
So, ![\Delta G=8.314\times 253\times ln(\frac{0.153}{0.555})mol/K](https://tex.z-dn.net/?f=%5CDelta%20G%3D8.314%5Ctimes%20253%5Ctimes%20ln%28%5Cfrac%7B0.153%7D%7B0.555%7D%29mol%2FK)
= -2710 J/mol
= -2.71 kJ/mol
Answer:
The bond angles between the axial bonding groups are slightly less than 180°.
The bond angles between the equatorial bonding groups are slightly less than 120°.
Explanation:
Accordign to VSEPR theory, a molecule with four bonding groups and one lone pair on the central atom has a trigonal bipyramidal electronic geometry.
The position of the lone pair can be located in the equatorial position or axial position.
When the lone pair is found in equatorial position, it has two axial groups that repel it and the angle of the lone pair between each axial group is 90°.
When the lone pair is in axial position it has 3 equatorial groups that repel it and the angle of the lone pair between each equatorial group is 90°.
Since the molecule has a lone pair, the most stable geometric structure is when the lone pair is in the equatorial position, because it has fewer repulsions than in the axial position.
The molecular geometry is "seesaw"
The bond angles between the axial bonding groups are slightly less than 180°.
The bond angles between the equatorial bonding groups are slightly less than 120°.
The balanced reaction is:
<span>4Cr(s)+3O2 (g )= Cr2O3 (s)
Since we are not given the amount of any of the reactants, we assume we have one gram of chromium. Calculations are as follows:
1 g Cr ( 1 mol Cr / 52 g Cr ) ( 1 mol Cr2O3 / 4 mol Cr ) = <span>0.005 mol Cr2O3
</span></span>0.005 mol Cr2O3 (151.99 g Cr2O3 / 1 mol Cr2O3 ) = 0.7307 g <span>Cr2O3
</span>
Therefore, the theoretical yield for 1 gram of Cr is 0.005 mol Cr2O3 or 0.7307 g Cr2O3.