Answer:
0.8749 grams of hydrogen gas was formed from the reaction.
Explanation:
P = Pressure of hydrogen gad= 744 Torr = 0.98 atm
(1 atm = 760 Torr)
V = Volume of hydrogen gas= 11 L
n = number of moles of hydrogen gas= ?
R = Gas constant = 0.0821 L.atm/mol.K
T = Temperature of vapor = 27.0 °C = 300.15 K
Putting values in above equation, we get:
Using an ideal gas equation:


n = 0.4374 moles
Mass of 0.4374 moles of hydrogen gas:
0.4374 mol × 2 g/mol = 0.8749 g
0.8749 grams of hydrogen gas was formed from the reaction.
Butterflies are cold-blooded and need the light from the sun to warm the muscles they use to fly. Not only do butterflies like the sun, the plants the they thrive on need full direct sun. Most plants need at least 8 hours of sunlight to bloom properly and provide enough nectar.
Answer:
= 25.05°C
Explanation:
Given:
the value of ΔHcomb (heat of combustion) for dimethylphthalate (C10H10O4) is = 4685 kJ/mol.
mass = 0.905g of dimethylphthalate
molar mass = 194.18g dimethylphthalate
number of moles of dimethylphthalate = ???
= 21.5°C
= 6.15 kJ/°C
= ???
since we have our molar mass and mass of dimethylphthalate ;we can determine the number of moles as;
0.905g of dimethylphthalate × 
number of moles of dimethylphthalate = 0.000466 moles
Heat released = moles of dimethylphthalate × heat of combustion
= 0.000466 moles × 4685 kJ
= 21.84 kJ
∴ Heat absorbed by the calorimeter =

21.84 kJ =6.15 kJ/°C 
21.84 KJ = 
21.84 KJ =
- 132.225 kJ
21.84 KJ + 132.225 kJ = 
154.065 kJ = 
= 
=25.05°C
Exothermic reactions is where energy is released. Exothermic reactions are reactions that release energy into the environment in the form of heat. Exothermic reactions feel warm or hot or may even be explosive.