A person has a height of 65 inches You want to find out the height of
that person in centimeters. Which
unit conversion would you use?

1 inch = 2.54 centimeters

Explanation:

A conversion factor or unit conversion is used to change the units only without affecting the value.

1 inch = 2.54 centimeters

Given, height = 65 inches

So, the height of  that person in centimeters = 65 x 2.54

                                                                         = 165.1 cm    

Hence, the person's height in centimeters will be 165.1 cm.

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