Given is the ratio of conjugate base and conjugate acid of phosphoric acid. pH of a substance is the concentration of the hydrogen ions in its solution and higher this concentration lower is the value of pH.
pKa value is a measure of the strength of acid, it is the negative log of acid dissociation constant Ka.
Answer:
-30.7 kj/mol
Explanation:
The standard free energy for the given reaction that is the hydrolysis of ATP is calculated using the formula: ∆Go ’= -RTln K’eq
where,
R = -8.315 J / mo
T = 298 K
For reaction,
1. K′eq1=270,
∆Go ’= -RTln K’eq
= - 8.315 x 298 x ln 270
= - 8.315 x 298 x 5.59
= - 13,851.293 J / mo
= - 13.85 kj/mol
2. K′eq2=890
∆Go ’= -RTln K’eq
= - 8.315 x 298 x ln 890
= - 8.315 x 298 x 6.79
= - 16.82 kj/mol
therefore, total standard free energy
= - 13.85 + (-16.82)
= -30.7 kj/mol
Thus, -30.7 kj/mol is the correct answer.
Answer:

Explanation:
Density is found by dividing the mass by the volume.

The mass of the liquid is 12.7 grams.
We know that 15 mL of this liquid was added to a 50 mL graduated cylinder. Therefore, the volume is 15 mL. The 50 mL is not relevant, it only tells us about the graduated cylinder.

Substitute the values into the formula.

Divide.

Round to the nearest hundredth. The 6 in the tenth place tells us to round the 4 to a 5.

The density of the liquid is about 0.85 grams per milliliter and choice A is correct.
Refer to the diagram shown below.
The piston supports the same load W at both temperatures.
The ideal gas law is

where
p = pressure
V = volume
n = moles
T = temperature
R = gas constant
State 1:
T₁ = 20 C = 20+273 = 293 K
d₁ = 25 cm piston diameter
State 2:
T₂ = 150 C = 423 K
d₂ = piston diameter
Because V, n, and R remain the same between the two temperatures, therefore

If the supported load is W kg, then

Similarly,


Because p₁/p₂ = T₁/T₂, therefore

The minimum piston diameter at 150 C is 20.8 cm.
Answer: 20.8 cm diameter