4.48
pH=pKa+log([A-/HA])
25% deprotonated tells us that A- is .25 and that the rest (75% is protonated) thats .75.
4 = pKa + log

4 - log

= pKa
4.48=pKa
Answer:
A calculator has an endifiite shape because all of its atoms are touching each other
The new volume when pressure increases to 2,030 kPa is 0.8L
BOYLE'S LAW:
The new volume of a gas can be calculated using Boyle's law equation:
P1V1 = P2V2
Where;
- P1 = initial pressure (kPa)
- P2 = final pressure (kPa)
- V1 = initial volume (L)
- V2 = final volume (L)
According to this question, a 4.0 L balloon has a pressure of 406 kPa. When the pressure increases to 2,030 kPa, the volume is calculated as:
406 × 4 = 2030 × V2
1624 = 2030V2
V2 = 1624 ÷ 2030
V2 = 0.8L
Therefore, the new volume when pressure increases to 2,030 kPa is 0.8L.
Learn more about Boyle's law calculations at: brainly.com/question/1437490?referrer=searchResults