Answer:
La respuesta está en la explicación
Explanation:
Los átomos que no poseen ___<em>CARGA</em>____ son conocidos como ____<em>ÁTOMOS</em>____ ____<em>NEUTROS</em>_____. Los átomos que poseen carga se denominan ___<em>IONES</em>____, aquellos con carga positiva de llaman ____<em>PROTONES</em>____ y son aquellos que __<em>PIERDEN</em>__ electrones. Los ______<em>ANIONES</em>____ son aquellos con carga negativa y son los que _____<em>GANAN</em>___ electrones. Para todos los casos el valor de _<em>MASA</em>__ y _<em>NÚMERO ATÓMICO</em>_ permanecen iguales y son los que sacamos de la tabla periódica.
 
        
             
        
        
        
Answer:
The heat of vaporisation of methanol is "3.48 KJ/Mol"
Explanation:
The amount of heat energy required to convert or transform  1 gram of liquid to vapour is called heat of vaporisation
When 8.7 KJ of heat energy is required to vaporize 2.5 mol of liquid methanol.
Hence, for 1 mol of liquid methanol, amount of heat energy required to evaporate the methanol is =   
 = 3.48 KJ
So, the heat of vaporization 
Therefore, the heat of vaporization of methanol is 3.48KJ/Mol
 
        
             
        
        
        
Let's begin with the basic values  that will be used in the solution.
The formula of propane is C3H8. It is an alkane, a hydrocarbon with the general formula of CnH2n+2. Notice that hydrocarbons have only Carbon and Hydrogen atoms. Its molar mass (M) is 44 g. 
Molar Mass Calculation is done as like that
C=12 g/mol, H=1 g/mol. 1 mole propane has 3 moles Carbon atoms and 8 mole Hydrogen atoms. M(C3H8)= 3*12+ 8*1= 44 g
Combustion reaction of hydrocarbons gives carbon dioxide and water by releasing energy. That energy is called as enthalpy of combustion (ΔHc°).  
ΔHc° of propane equals -2202.0 kj/mol. Burning of 1 mole C3H8 releases 2202 kj energy. Minus sign only indicates that the energy is given out ( an exothermic reaction ).
Let's write the combustion reaction.
C3H8 + O2 ---> CO2 + H20 (unbalanced) ΔHc° = -2202 kj/mol
Now, we calculate mole of 20 kg propane. Convert kilogram into gram since we use molar mass is defined in grams.
mole=mass/molar mass ; n=m/M ; n= 20000 g /44 (g/mol)=454 mole
1 mole propane releases 2202 kj energy.
454 mole propane release 2202 kj *454= 1000909 kj
The answer is 1000909 kj.
        
             
        
        
        
Answer:
An increase in entropy
Explanation:
In ice, the molecules are very well ordered because of the H-bonds. As ice melts, the intermolecular forces are broken (requires energy), but the order is interrupted (so entropy increases). Water is more random than ice, so ice spontaneously melts at room temperature.
Just think about this rationally. Melting ice (or anything) will require heat put in (this is called the latent heat of fusion), so you automatically know that the change in enthalpy is going to be positive. In order to make the reaction spontaneous, delta G, the Gibbs free energy has to be negative. So now look at the formula Delta(G) = Delta(H) - T*Delta*(S). If you know that g is negative, and H is positive, then it is only possible if -T*Delta(S) is negative. If that is positive, then Delta(S) has to be positive. So theres your answer :). An increase in entropy
 
        
             
        
        
        
<span>Important information to solve the exercise :
Substance	ΔHf (kJ/mol):
HCl(g)=	−92.0 </span><span>kJ/mol
Al(OH)3(s)=	−1277.0 </span><span><span>kJ/mol
</span> H2O(l)=	−285.8 </span><span>kJ/mol
AlCl3(s)	=−705.6 </span><span>kJ/mol
</span><span>Al(OH)3(s)+3HCl(g)→AlCl3(s)+3H2O(l)
    reactants                         products
products- reactants:</span><span>
(−705.6) + (3 x −285.8) - ( −1277.0 ) - (3 x −92.0 ) = - 10.0 </span>kJ per mole at 25°C
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