Using Hess's Law rearrange the fiven reactions to determine the heat of reaction for Fe2O3(s) + 3 CO(g) --> 2 Fe(s) + 3 CO2(g)

Explain waht needs to ve done to each reaction to determine the final reaction desired

reaction 1: 2 Fe(s) + 3/2 O2(g) --> Fe2O3(s) ^H = -824.2 KJ/mol

reaction 2: CO(g) + 1/2 O2(g) --> 2 CO2(g) ^H = -282.7 KJ

First reaction: ^ H becomes KJ/mol

second reaction ^H becomes KJ/mol

heat of reaction is KJ/mol

a 20-cm-long, cylindrical graphite (pure carbon) rod is inserted into an oxidizing atmosphere at 1145 k and 1.013 x 105 pa pressure. the oxidizing process is limited by the diffu- sion of oxygen counterflow to the carbon monoxide that is formed on the cylindrical surface.

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

the population of unionid mussels in the hudson river decreased after zebra mussels were introduced. zebra mussels, a nonnative species, competed with the unionid mussels for food. the zebra mussels were able to outcompete the unionid mussels, allowing the zebra mussel population to increase dramatically over six years. the unionid mussel population decreased due to a lack of food.

hope this :