Answer:
pH = 12.8
Explanation:
HF + NaOH → F⁻ + Na⁺ + H₂O
<em>1 mole of HF reacts with 1 mole of NaOH</em>
<em />
Initial moles of HF and NaOH are:
HF = 0.018L × (0.308mol / L) = 5.544x10⁻³mol HF
NaOH = 0.023L × (0.361mol / L) = 8.303x10⁻³mol NaOH
That means moles of NaOH remains after reaction are:
8.303x10⁻³mol - 5.544x10⁻³mol = <em>2.759x10⁻³moles NaOH</em>
Total volume is 18.0mL + 23.0mL = 41.0mL = 0.0410L
Molar concentration of NaOH is
2.759x10⁻³moles NaOH / 0.0410L = 0.0673M = [OH⁻]
pOH = - log [OH⁻] = 1.17
As pH = 14 - pOH
<em>pH = 12.8</em>
<em></em>
Answer:49.3
Explanation:4.1j/g c * 25g * (t2-45c)=455j
T2-45c = 455j/4.1j/g c * 25g
455/104.6
45+4.3= 49.3 celsius
The approximate partial pressure of oxygen at 1500 m is 0.18 atm.
<h3>Pressure of the air</h3>
From barometric pressure table;
1500 m = 85 kPa
1 kPa = 0.0099 atm
85 kPa = ?
= 0.84 atm
Oxygen percentage in air = 21%
<h3>Partial pressure of oxygen in air</h3>
P = 0.21 x P(total)
P = 0.21 x 0.84 atm
P = 0.18 atm
Thus, the approximate partial pressure of oxygen at 1500 m is 0.18 atm.
Learn more about partial pressure here: brainly.com/question/19813237
#SPJ11
Lithium heparin tube i think, could be wrong but i think this is right.
