In the bloodstream, the effective pKa for carbonic acid is 6.35. If the pH of the blood is 7.40, what percentage of the blood buffer is present as bicarbonate

The 91.8% is present as bicarbonate ion

Explanation:

It is possible to find pH of a buffer using H-H equation:

pH = pKa + log [A⁻] / [HA]

Where pH is 7.40; pKa is 6.36, [A⁻] is concentration of bicarbonate ion and [HA] concentration of carbonic acid

7.40 = 6.35 + log [A⁻] / [HA]

1.05 = log [A⁻] / [HA]

11.22 = [A⁻] / [HA] (1)

As the question is in therms of percentage:

[A⁻] + [HA] = 100 (2)

Replacing (2) in (1):

11.22 = [A⁻] / 100 - [A⁻]

1122 - 11.22[A⁻] = [A⁻]

1122 = 12.22[A⁻]

91,8% = [A⁻]

samuel de champlain. in 1608, king henry iv sponsored pierre dugua, sieur de mons and samuel de champlain as founders of the city of quebec with 28 men. this was the second permanent french settlement in the colony of canada.

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j