Someone please help!! A pycnometer is a glass apparatus used for accurately determining the density of a liquid.

When dry and empty, a certain pycnometer had a mass of 27.056 g. When filled with distilled water at 25.0°C, it weighed 36.773 g.

When filled with chloroform, the apparatus weighed 41.451 g. At 25.0°C, the density of water is 0.99704 g/mL

What is the volume of the pycnometer?

The Taj Mahal

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