Answer:
A. Wax drips down the side of a lot candle.
Explanation:
The chemical change from solid to liquid. This is a combustion reaction, so carbon dioxide gas and water vapour is also produced but you can't see them
A) can enter from the surroundings, but cannot escape to the surroundings
Answer:
600K
Explanation:
PV=nRT
T=PV/nR
= 1.6atm* 15.0L/ 0.5mol*0.0821LatmK^-1mol^-1
=600K
Answer:
The formula is H202 (hydrogen peroxide, known as hydrogen peroxide)
Explanation:
100%----34g
5, 9783%---X= (5, 9783%x 34g)/100% =2 g
1g---1 atom of H
2g----x= 2g x 1 atom of H/1g = 2 atom of H
100%----34g
94, 0217%---X= (94,0217%x 34g)/100% =32 g
16g---1 atom of 0
32g----x= 32g x 1 atom of 0/16g = 2 atom of 0
Enthalpy of formation is calculated by subtracting the total enthalpy of formation of the reactants from those of the products. This is called the HESS' LAW.
ΔHrxn = ΔH(products) - ΔH(reactants)
Since the enthalpies are not listed in this item, from reliable sources, the obtained enthalpies of formation are written below.
ΔH(C2H5OH) = -276 kJ/mol
ΔH(O2) = 0 (because O2 is a pure substance)
ΔH(CO2) = -393.5 kJ/mol
ΔH(H2O) = -285.5 kJ/mol
Using the equation above,
ΔHrxn = (2)(-393.5 kJ/mol) + (3)(-285.5 kJ/mol) - (-276 kJ/mol)
ΔHrxn = -1367.5 kJ/mol
<em>Answer: -1367.5 kJ/mol</em>
