Answer:
1.788 C DEGREES
Explanation:
STP is 1 atm at 273.15 K
P1V1/T1 = P2V2/T2
(1)(62.65) / (273.15) = (612/760)(78.31)/T2
T2 = 274.93 K = 1.788 C
Answer:
8 to 1.
Explanation:
- Oxygen combines with hydrogen atoms to form water according to the balanced equation:
<em>O₂ + 2H₂ → 2H₂O.</em>
It is clear that one mole of oxygen combines with two moles of hydrogen atoms to form 2 moles of water.
So, the molar ratio of oxygen to hydrogen is (1 to 2).
- The mass of 1 mole of oxygen = (no. of moles)(molar mass) = (1 mol)(32.0 g/mol) = 32.0 g.
- The mass of 2 moles of hydrogen = (no. of moles)(molar mass) = (2 mol)(2.0 g/mol) = 4.0 g.
<em>So, the mass ratio of oxygen to hydrogen (32.0 g/4.0 g) = (8: 1).</em>
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The combustion reaction is as expressed,
CxHy + O2 --> CO2 + H2O
The mass fraction of carbon in CO2 is 3/11. Hence,
mass of C in CO2 = (3.14 g)(3/11) = 0.86 g C.
Given that we have 1 g of the hydrocarbon, the mass of H is equal to 0.14 g.
moles of C = 0.86 g C / 12 g = 0.0713
moles of H = 0.14 g H / 1 g = 0.14
The empirical formula for the hydrocarbon is therefore, CH₂.
Generally speaking a precipitate is something that will form as a result of the reaction. It generally is a solid material.
Sodium and nitrates are soluble so Calcium Phosphate would precipitate out....
your answer is <u>D</u><u>.</u><u> </u>physical change, because a new substance is not formed.
