Question

A chemist measures the enthalpy change ?H during the following reaction: Fe (s) + 2HCl (g) ? FeCl2 (s) + H2 (g) =?H?157.kJ Use this information to complete the table below. Round each of your answers to the nearest /kJmol .

reaction?H

?2Fe(s)+4HCl(g)-->2FeCl2(s)+2H2(g) = __ kJ

?4FeCl2(s)+4H2(g)-->4Fe(s)+8HCl(g) = ___ kJ

?FeCl2(s)+H2(g)-->Fe(s)+2HCl(g) = ___ kJ

Answer 1

Correct Question:

A chemist measures the enthalpy change ΔH during the following reaction: Fe(s) + 2HCl(g)-->FeCl2(s) + H2 ΔH=-157.0 kJ. Use this information to complete the table below. Round each of your answers to the nearest kJ/mol

Answer:

-314 kJ

+628 kJ

+157 kJ

Explanation:

The enthalpy change of a reaction measures the amount of heat that is lost or gained by it. If ΔH >0 the heat is gained, and the reaction is called endothermic, if ΔH<0, the heat is lost, and the reaction is called exothermic.

If the reaction is inverted, the value of ΔH is inverted too (the opposite endothermic reaction is exothermic), and if the reaction is multiplied by a constant, ΔH will be multiplied by it too.

1) 2Fe(s) + 4HCl --> 2FeCl2(s) + 2H2(g)

This reaction is the product of the given reaction by 2, so

ΔH = 2*(-157) = -314 kJ

2) 4FeCl2(s) + 4H2(g) --> 4Fe(s) + 8HCl(g)

This reaction is the inverted reaction given multiplied by 4, so

ΔH = 4*(157) = +628 kJ

3) FeCl2(s) + H2(g) --> Fe(s) + 2HCl

This reaction is the inverted reaction given, so

ΔH = +157 kJ

Answer 2

The enthalpy of the 1st reaction is -314 kJ, 2nd reaction is +628 kJ, and 3rd reaction is +157 kJ.

The enthalpy of the reaction can be given as the energy gained or lost by the reaction.

The given reaction has 1 Fe combined with 2 HCl to give 2 Iron chloride and 1 hydrogen. The enthalpy for the reaction is -157 kJ.

A. $\rm 2\;Fe\;+\;4\;HCl\;\rightarrow\;2\;FeCl_2\;+\;2\;H_2$

The reaction has been double the given reaction. Thus, the enthalpy has been doubled.

Enthalpy = 2 $\times$ -157 kJ

Enthalpy = -314 kJ

B. $\rm 4\;FeCl_2\;+\;4\;H_2\;\rightarrow\;4\;Fe\;+\;8\;HCl$

The reaction has been the opposite of the given reaction with the product factor 4.

The enthalpy has a +ve sign.

Enthalpy = 4  $\times$ 157 kJ

Enthalpy = 628 kJ

C. $\rm FeCl_2\;+\;H_2\;\rightarrow\;Fe\;+\;2\;HCl$

The reaction has been the inverted reaction, and the enthalpy will be +157 kJ.

For more information about the enthalpy of reaction, refer to the link:

https://brainly.com/question/1657608