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3 years ago

Grade 8 Science

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Cuando se quema 1 mol de metano –o sea, 16 g–, se desprenden 802

Anvisha [2.4K]

Answer:

1 gramo de metano aporta 50.125 kilojoules.

1 gramo de metano aporta 48.246 kilojoules.

Explanation:

La cantidad de energía liberada por la combustión de una unidad de masa del hidrocarburo ( $Q$ ), en kilojoules por mol, es igual a la cantidad de energía liberada por mol de compuesto ( $\bar {Q}$ ), en kilojoules por mol, dividido por su masa molar ( $M$ ), en gramos por mol:

$Q = \frac{\bar Q}{M}$ (1)

A continuación, analizamos cada caso:

Metano

$Q = \frac{802\,\frac{kJ}{mol} }{16\,\frac{g}{mol} }$

$Q = 50.125\,\frac{kJ}{g}$

1 gramo de metano aporta 50.125 kilojoules.

Octano

$Q = \frac{5500\,\frac{kJ}{mol} }{114\,\frac{g}{mol} }$

$Q = 48.246\,\frac{kJ}{mol}$

1 gramo de metano aporta 48.246 kilojoules.

3 0

3 years ago

A chemist fills a reaction vessel with 9.20 atm nitrogen monoxide (NO) gas, 9.15 atm chlorine (CI) gas, and 7.70 atm nitrosyl ch

ivanzaharov [21]

Answer:

The reactions free energy $\Delta G = -49.36 kJ$

Explanation:

From the question we are told that

The pressure of (NO) is $P_{NO} = 9.20 \ atm$

The pressure of (Cl) gas is $P_{Cl} = 9.15 \ atm$

The pressure of nitrosly chloride (NOCl) is $P_{(NOCl)} = 7.70 \ atm$

The reaction is

$2NO_{(g)} + Cl_2 (g)$ ⇆ $2 NOCl_{(g)}$

From the reaction we can mathematically evaluate the $\Delta G^o$ (Standard state free energy ) as

$\Delta G^o = 2 \Delta G^o _{NOCl} - \Delta G^o _{Cl_2} - 2 \Delta G^o _{NO}$

The Standard state free energy for NO is constant with a value

$\Delta G^o _{NO} = 86.55 kJ/mol$

The Standard state free energy for $Cl_2$ is constant with a value

$\Delta G^o _{Cl_2} = 0kJ/mol$

The Standard state free energy for $NOCl$ is constant with a value

$\Delta G^o _{NOCl} =66.1kJ/mol$

Now substituting this into the equation

$\Delta G^o = 2 * 66.1 - 0 - 2 * 87.6$

$= -43 kJ/mol$

The pressure constant is evaluated as

$Q = \frac{Pressure \ of \ product }{ Pressure \ of \ reactant }$

Substituting values

$Q = \frac{(7.7)^2 }{(9.2)^2 (9.15) } = \frac{59.29}{774.456}$

$= 0.0765$

The free energy for this reaction is evaluated as

$\Delta G = \Delta G^o + RT ln Q$

Where R is gas constant with a value of $R = 8.314 J / K \cdot mol$

T is temperature in K with a given value of $T = 25+273 = 298 K$

Substituting value

$\Delta G = -43 *10^{3} + 8.314 *298 * ln [0.0765]$

$= -43-6.36$

$\Delta G = -49.36 kJ$

4 0

3 years ago

1-The chemical potential energy of bond A is greater than the chemical potential energy of bond B. Which statement best explains

Tju [1.3M]

It should be noted that bond A has greater energy because C. The atoms in bond A are held more tightly together than the atoms in bond B.

The relationship between the bond energies of nitrogen, iodine, and fluorine gases is that the bond in nitrogen gas is the most difficult to break.

From the information given, the molecule with the greatest bid energy is CH4. The bind energy measures the bond strength that the chemical bond has.

Also, the bond energy of the reactants in reaction 1 is greater than the bond energy of the reactants in reaction 2. Due to this, reaction 1 requires a greater input of energy than reaction 2.

Lastly, the difference in the bond energy of Chlorine and Bromine is that Bromine has more electron levels than chlorine.

Learn more about bonds on:

brainly.com/question/819068

6 0

3 years ago

Read 2 more answers

A geologist is making observations from atop a small mountain. She sees two parallel faults: one directly to the east and one di

GenaCL600 [577]

Answer:

Fault-block mountain

Explanation:

I got it right on the assignment