<span>5.75 moles
The formula for methyl tert-butyl ether is (CH3)3COCH3, so a single molecule has 5 carbon, 12 hydrogen, and 1 oxygen atoms. So for every 12 moles of hydrogen, there's 1 mole of oxygen. So simply divide the number of moles of hydrogen by 12 to get the number of moles of oxygen.
69.0 / 12 = 5.75
Therefore there's 5.75 moles of oxygen in the sample.</span>
This problem is providing us with the mass of propane, its enthalpy of combustion, and the initial and final temperature of water that can be heated from the burning of this fuel. At the end, the result turns out to be 42.27 L.
<h3>Combustion:</h3>
In chemistry, combustion reactions are based on the burning of fuels by using oxygen and producing both carbon dioxide and water. For propane, we will have:

Hence, we can calculate the heat released from this reaction by using the mass, which has to be converted to moles, and the given enthalpy of combustion:

<h3>Calorimetry:</h3>
In chemistry, we can analyze the mass-specific heat-temperature-heat relationship via the most general heat equation:

Thus, since Q was obtained from the previous problem, but the sign change because the released heat is now absorbed by the water, one can calculate the mass of water that rises from 20.0°C to 100.0°C with this heat:

Finally, we convert it to liters as required:

Learn more about calorimetry: brainly.com/question/1407669
D, Urine.
Just google what sweat is made of and it gives you all of the answers except for urine. Also you’d probably smell really bad if your sweat had urine in it. Hope this helps! :)
Answer:
pH of the benzoic acid solution = 3.35
Explanation:
Benzoic acid is a weak monoprotic acid
pKa = 4.2
⇒ Ka = 6.3 x 10⁻⁵
C₆H₅COOH ⇄ C₆H₅COO⁻ + H⁺
Initial concentration C molar 0 0
At equilibrium (c - cα) cα cα
Acid dissociation constant Ka = 
⇒ 6.3 x 10⁻⁵ = α²c ................(1)
(for weak electrolyte 1 -α = 1)
Concentration of benzoic acid C = 25 x 0.126 x 10⁻³ = 0.00315 molar
From eqn (1)
α² = 
⇒ α = √(
)
⇒ α = 0.14
So concentration of H⁺ ion = 0.14 x 0.00315 = 0.000441
pH = - log 0.000441 = 3.35
We not considered H⁺ concentration of water because pH < 7
Answer:
500 cubic centimeters of water