<h2>Question:</h2>
What percentage of the Earth's surface is covered by oceans?
<h2>Answer:</h2>
<u>71</u><u> </u><u>percentage</u><u> </u>
<h2>
<u>#CARRYONLEARNING</u><u> </u></h2><h2>
<u>#STUDYWELL</u><u> </u></h2>
Explanation:
done.....................
The pH of the solution created is 7.21
<u>Explanation:</u>
Ka1 = 6.9 X 10⁻³
Ka2 = 6.2 X 10⁻⁸
Ka3 = 4.8 X 10⁻¹³
pKa = - log( Ka)
Thus,
pKa1 = - log ( 6.9 X 10⁻³) = 2.16
pKa2 = - log ( 6.2 X 10⁻⁸ ) = 7.21
pKa3 = - log ( 4.8 X 10⁻¹³ ) = 12.3
KH₂PO₄ + Na₂HPO₄ = KH₃PO₄ + Na₂PO₄
Ka2 = [ KH₃PO₄] [Na₂PO₄] / [KH₂PO₄] [Na₂HPO₄]
log (Ka2 ) = log [[ KH₃PO₄] [Na₂PO₄] / [KH₂PO₄] [Na₂HPO₄]]
pH = pKa2 + log [KH₂PO₄] /[Na₂HPO₄] = 7.21
Therefore, the pH of the solution created is 7.21
Answer: 0.24 moles
Explanation: Using IDEAL GAS LAW
PV=nRT
where,
P = pressure of the gas= 2.0 atm
V = volume of the gas= 3.00L
T =Temperature of gas=25^0C=(25+273)K=298K
n = number of moles of gas=?
R = Gas constant = 0.0821 Latm/moleK
n=\frac {PV}{RT}=\frac {2.0\times 3.0}{0.0821\times 298}=0.24moles