Answer: The correct answer is -297 kJ.
Explanation:
To solve this problem, we want to modify each of the equations given to get the equation at the bottom of the photo. To do this, we realize that we need SO2 on the right side of the equation (as a product). This lets us know that we must reverse the first equation. This gives us:
2SO3 —> O2 + 2SO2 (196 kJ)
Remember that we take the opposite of the enthalpy change (reverse the sign) when we reverse the equation.
Now, both equations have double the coefficients that we would like (for example, there is 2S in the second equation when we need only S). This means we should multiply each equation (and their enthalpy changes) by 1/2. This gives us:
SO3 —>1/2O2 + SO2 (98 kJ)
S + 3/2O2 —> SO3 (-395 kJ)
Now, we add the two equations together. Notice that the SO3 in the reactants in the first equation and the SO3 in the products of the second equation cancel. Also note that O2 is present on both sides of the equation, so we must subtract 3/2 - 1/2, giving us a net 1O2 on the left side of the equation.
S + O2 —> SO2
Now, we must add the enthalpies together to get our final answer.
-395 kJ + 98 kJ = -297 kJ
Hope this helps!
Number 1 is incorrect, the genotypes are given to you. You need to use GG and gg. The outcome would be 100% Gg.
Number 2 is incorrect, the genotypes are given to you. You need to use Gg and Gg. The outcome would be 25% gg, 25% GG, and 50% Gg.
Number 3 is incorrect, the genotypes are given to you. You need to use TT and tt. The outcome would be 100% Tt.
Number 4 is incorrect, the genotypes are given to you. You need to use RR and rr. The outcome would be 100% Rr.
Please read the directions and use the genotypes they give you! The information is all there for you, you just need to put it in correctly. If you're still having trouble understanding how to do this, feel free to message me and I'd be happy to help you.
Answer:
53.9 g
Explanation:
When talking about buffers is very common the problem involves the use of the Henderson Hasselbach formula:
pH = pKa + log [A⁻]/[HA]
where [A⁻] is the concentration of the conjugate base of the weak acid HA, and [HA] is the concentration of the weak acid.
We can calculate pKₐ from the given kₐ ( pKₐ = - log Kₐ ), and from there obtain the ratio [A⁻]/HA].
Since we know the concentration of HC6H5CO2 and the volume of solution, the moles and mass of KC6H5CO2 can be determined.
So,
4.63 = - log ( 6.3 x 10⁻⁵ ) + log [A⁻]/[HA] = - (-4.20 ) + log [A⁻]/[HA]
⇒ log [A⁻]/[HA] = 4.63 - 4.20 = log [A⁻]/[HA]
0.43 = log [A⁻]/[HA]
taking antilogs to both sides of this equation:
10^0.43 = [A⁻]/[HA] = 2.69
[A⁻]/ 1.00 M = 2.69 ⇒ [A⁻] = 2.69 M
Molarity is moles per liter of solution, so we can calculate how many moles of C6H5CO2⁻ the student needs to dissolve in 125. mL ( 0.125 L ) of a 2.69 M solution:
( 2.69 mol C6H5CO2⁻ / 1L ) x 0.125 L = 0.34 mol C6H5CO2⁻
The mass will be obtained by multiplying 0.34 mol times molecular weight for KC6H5CO2 ( 160.21 g/mol ):
0.34 mol x 160.21 g/mol = 53.9 g
Answer:
1) correct
2) incorrect
3) correct
4)incorrect
Explanation:
1) A Lewis acid is a substance that accepts a nonbonding pair of electrons.
A Bronsted-Lowry acid is a substance that donates a proton H⁺
Since the donation of a proton involves the acceptance of a pair of electrons, every Bronsted-Lowry acid is also a Lewis acid.
2)A Lewis acid not necessarily needs to have a proton to be donated.
3) Conjugated acids of weak bases are strong acids and conjugated acids of strong bases are weak acids.
4)K⁺ comes from a strong base, therefore is does not have an acidic behaviour.
