How many grams of ar are there in 2.25 moles of ar?

89.88 g

Explanation:

Atomic Mass of Ar: 39.948

Mass = moles * AM

Replacing moles = 2.25 and AM = 39.948 you get the mass of Ar:

Mass = 2.25 * 39.948

Mass = 89.88 g

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