Answer:
Empirical formula is Li₂CO₃.
Explanation:
Percentage of oxygen= 65.0%
Percentage of lithium = 18.7%
Percentage of carbon= 16.3%
Empirical formula = ?
Solution:
Number of gram atoms of C = 16.3/12 = 1.4
Number of gram atoms of Li = 18.7/6.94 = 2.7
Number of gram atoms of O = 65.0/ 16 = 4.1
Atomic ratio:
Li : C : O
2.7/1.4 : 1.4/1.4 : 4.1/1.4
2 : 1 : 3
Li : C : O = 2 : 1 : 3
Empirical formula is Li₂CO₃.
Check the attached file for the answer.
Answer:
4.34.
Explanation:
<em>∵ pH = pKa + log [salt]/[Acid]</em>
∴ pH = - log(Ka) + log [salt]/[Acid]
∴ pH = - log(6.8 x 10⁻⁵) + log(0.75)/(0.50)
<em>∴ pH = 4.167 + 0.176 = 4.343 ≅ 4.34.</em>
<em></em>
q = mCΔT
The correct specific heat capacity of water is <em>4.187 kJ/(kg.K)</em>.
ΔT = q/mC = 87 kJ/[648.00 kg x 4.187 kJ/(kg.K)] = 87 kJ/(2713 kJ/K) = 0.032 K
Tf = Ti + ΔT = 298 K + 0.032 K = 298.032 K
<span>We breathe around an average of 500 ml of air in 1 normal (or relax) breathing. The lungs already have around 3 litres of reserve breathing. Since there is around 21% oxygen in air, we breathe in around 105 ml of Oxygen from the air. That is equal to around 0.14 g of Oxygen.</span>