Mass, charge, and energy are conserved, no matter how much volume of
space they may be spread through either before or after the reaction.
Concerning density ...
Think about the fascinating classroom demonstration where the teacher
drops a tiny pellet of sodium into a glass of water. The sodium gets very
excited, and it skates and skitters around on the surface of the water,
faster and faster, and eventually it explodes. All the girls in the class
scream, while the guys are just sitting there and staring at the cloud
of steam that's rising from the glass of water. The whole point here
is that the density of the steam is much different from the density of
either the water or the sodium that reacted to create it. The density
is not conserved.
Answer : The energy removed must be, -67.7 kJ
Solution :
The process involved in this problem are :
The expression used will be:
![\Delta H=[m\times c_{p,g}\times (T_{final}-T_{initial})]+m\times \Delta H_{vap}+[m\times c_{p,l}\times (T_{final}-T_{initial})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Bm%5Ctimes%20c_%7Bp%2Cg%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D%2Bm%5Ctimes%20%5CDelta%20H_%7Bvap%7D%2B%5Bm%5Ctimes%20c_%7Bp%2Cl%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D)
where,
= heat released by the reaction = ?
m = mass of benzene = 125 g
= specific heat of gaseous benzene = 
= specific heat of liquid benzene = 
= enthalpy change for vaporization = 
Molar mass of benzene = 78.11 g/mole
Now put all the given values in the above expression, we get:
![\Delta H=[125g\times 1.06J/g.K\times (353.0-(425.0))K]+125g\times -434.0J/g+[125g\times 1.73J/g.K\times (335.0-353.0)K]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B125g%5Ctimes%201.06J%2Fg.K%5Ctimes%20%28353.0-%28425.0%29%29K%5D%2B125g%5Ctimes%20-434.0J%2Fg%2B%5B125g%5Ctimes%201.73J%2Fg.K%5Ctimes%20%28335.0-353.0%29K%5D)
Therefore, the energy removed must be, -67.7 kJ
The reactants are methane and oxygen.
The products are carbon dioxide and water.
Hey there!
Volume in mL :
1.68 L * 1000 => 1680 mL
Density = 0.921 g/mL
Therefore:
Mass = density * Volume
Mass = 0.921 * 1680
Mass = 1547.28 g
The compound NaH2PO4 name is
sodium dihydrogen phosphate
Explanation
This name is arrived at by using the IUPAC rules of naming compound
1. the metal (sodium)is named first followed by the ligand ( hydrogen and phosphate)
Ligand are molecules that are attached to the metal center.
2. ligand are named using alphabetical order(for our case h for hydrogen come before p for phosphate hence hydrogen is named first)
3. Prefix di is used since hydrogen are two
hence the name of the compound is Sodium dihydrogen phosphate
