Answer:
a) [A⁻]/[HA] = 0.227
b) [A⁻]/[HA] = 0.991
c) [A⁻]/[HA] = 2.667
Explanation:
In the Henderson-Hasselbalch equation, HA stands from an acid an A⁻ stands from its conjugate base, as follows:
pH = pka + Log [A⁻]/[HA]
pH = 4.874 + Log[CH₃CH₂CO₂⁻]/[CH₃CH₂CO₂H]
4.23 = 4.874 + Log [A⁻]/[HA]
-0.644 = Log [A⁻]/[HA]
= [A⁻]/[HA]
0.227 = [A⁻]/[HA]
4.87 = 4.874 + Log [A⁻]/[HA]
-0.004 = Log [A⁻]/[HA]
= [A⁻]/[HA]
0.991 = [A⁻]/[HA]
5.30 = 4.874 + Log [A⁻]/[HA]
0.426 = Log [A⁻]/[HA]
= [A⁻]/[HA]
2.667 = [A⁻]/[HA]
To determine the standard heat of reaction, ΔHrxn°, let's apply the Hess' Law.
ΔHrxn° = ∑(ν×ΔHf° of products) - ∑(ν×ΔHf° of reactants)
where
ν si the stoichiometric coefficient of the substances in the reaction
ΔHf° is the standard heat of formation
The ΔHf° for the substances are the following:
CH₃OH(l) = -238.4 kJ/mol
CH₄(g) = -74.7 kJ/mol
O₂(g) = 0 kJ/mol
ΔHrxn° = (1 mol×-74.7 kJ/mol) - ∑(1 mol×-238.4 kJ/mol)
ΔHrxn° = +163.7 kJ
Answer:
the third one, measured or observed without changing the identity and composition of matter. because physical property does not under go any change but can be put back.
Answer:
-2, -1, 0, 1, 2
Explanation:
There are four types of quantum numbers;
1) Principal quantum number (n)
2) Azimuthal quantum number (l)
3) magnetic quantum number (ml)
4) Spin quantum number (s)
The azimuthal quantum number (l) describes the orbital angular momentum and shape of an orbital while the magnetic quantum number shows the projections of the orbital angular momentum along a specified axis. This implies that the magnetic quantum number shows the orientation of various orbitals along the Cartesian axes. The values of the magnetic quantum number ranges from -l to + l
For l= 2, the possible values of the magnetic quantum number are; -2, -1, 0, 1, 2
A. Thermal energy good job
