A substance releases 2,192 J of heat, changing its temperature from 50 degrees C to 5 degrees C. The mass of the substance is 73
1 answer:
The specific heat capacity of the given substance is -0.66 J/g°C.
<u>Explanation:</u>
The heat absorbed by any substance is the product of its mass, specific heat capacity and change in temperature.
q = m × c × ΔT
m is the mass in grams
q = amount of heat released or absorbed in J
ΔT = change in temperature in °C = 5 -50 = -45°C
c = specific heat capacity in J/g°C
c =
Plugin the values, we will get,
c =
= -0.66 J/g°C
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Answer:
17.65 grams of O2 are needed for a complete reaction.
Explanation:
You know the reaction:
4 NH₃ + 5 O₂ --------> 4 NO + 6 H₂O
First you must know the mass that reacts by stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction). For that you must first know the reacting mass of each compound. You know the values of the atomic mass of each element that form the compounds:
- N: 14 g/mol
- H: 1 g/mol
- O: 16 g/mol
So, the molar mass of the compounds in the reaction is:
- NH₃: 14 g/mol + 3*1 g/mol= 17 g/mol
- O₂: 2*16 g/mol= 32 g/mol
- NO: 14 g/mol + 16 g/mol= 30 g/mol
- H₂O: 2*1 g/mol + 16 g/mol= 18 g/mol
By stoichiometry, they react and occur in moles:
- NH₃: 4 moles
- O₂: 5 moles
- NO: 4 moles
- H₂O: 6 moles
Then in mass, by stoichiomatry they react and occur:
- NH₃: 4 moles*17 g/mol= 68 g
- O₂: 5 moles*32 g/mol= 160 g
- NO: 4 moles*30 g/mol= 120 g
- H₂O: 6 moles*18 g/mol= 108 g
Now to calculate the necessary mass of O₂ for a complete reaction, the rule of three is applied as follows: if by stoichiometry 68 g of NH₃ react with 160 g of O₂, 7.5 g of NH₃ with how many grams of O₂ will it react?
mass of O₂≅17.65 g
<u><em>17.65 grams of O2 are needed for a complete reaction.</em></u>
Answer:
Explanation:
Hello,
In this case, for us to compute the final volume we apply the Boyle's law that analyzes the pressure-volume temperature as an inversely proportional relationship:
So we solve for by firstly computing the initial pressure:
Finally, we can compute the work by using the following formula:
Best regards.