A 28.5 gram piece of iron is added to a graduated cylinder containing 45.5 mL of water. The water in the cylinder rises to the 49.1 mark. Calculate the density of the iron piece.

7.91 g/ml is the density of the iron piece of 28.5 gms.

Explanation:

The density of a substance is defined as the volume it occupies.  It tells the matter present in a substance.

The density is mass per unit volume and is denoted by p.

The formula for density is given by:

density (p) =

Data given is :

mass= 28.5 grams

V1 = 45.5 ml

V2= 49.1 ml

The initial volume of water was 45.5 ml, when iron piece of 28.5 grams was added the final volume was 49.1 ml.

Putting the values in the equation of density

p =

p = 7.91 g/ml

Since iron is a dense material it will occupy less volume

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"