4. Write the balanced equation for CH4+Cl2„_CH2Cl2+HCl6. For the reaction in problem 4, Heat of Reaction = -118.3 kcal/mol. Identify whether this is an exothermic or endothermic reaction. Calculate the Heat of Reaction when 6.00 g of Cl2 are used in the reaction.

CH4+ 2Cl2 --> CH2Cl2 + 2HCl + heat

The - sign for delta H tells you it is an exothermic reaction. Delta H is -118.3 kcal/mol which tell you that 137.8g(4 x35.45) of Cl2 gives 118.3 kcal. So how much will 6 g give you?

10kcal?

To write the balanced equation for the reaction, we start by identifying the elements in each molecule and ensuring that the number of atoms on both sides of the equation is equal.

CH4 + Cl2 → CH2Cl2 + HCl

To determine whether the reaction is exothermic or endothermic, we need to look at the sign of the heat of reaction. If the heat of reaction is negative, it is an exothermic reaction, indicating that heat is released. If the heat of reaction is positive, it is an endothermic reaction, meaning that heat is absorbed.

Given that the heat of reaction is -118.3 kcal/mol, we can conclude that the reaction is exothermic.

To calculate the heat of reaction when 6.00 g of Cl2 is used, we need to convert the mass of Cl2 to moles using the molar mass of Cl2, which is 70.91 g/mol.

First, calculate the number of moles of Cl2:
moles = mass / molar mass
moles = 6.00 g Cl2 / 70.91 g/mol = 0.085 mol Cl2

Based on the balanced equation, the stoichiometric coefficient of Cl2 is 1. Therefore, the heat of reaction in the given question corresponds to 1 mole of Cl2.

To calculate the heat of reaction when 0.085 mol of Cl2 is used, we can use the following ratio:

(Heat of Reaction with 6.00 g of Cl2) = (Heat of Reaction with 1 mole of Cl2) × (moles of Cl2 used)

Heat of Reaction with 6.00 g of Cl2 = -118.3 kcal/mol × 0.085 mol Cl2 = -10.05 kcal

Therefore, the heat of reaction when 6.00 g of Cl2 is used is approximately -10.05 kcal.