<span>2 NaOH(aq)+ 2 Al(s)+ 2 H</span>₂<span>O → 2 NaAlO</span>₂<span>(aq)+ 3 H</span>₂<span>(g)
</span> 2mol : 2mol : 3mol
2,14mol : 1,89mol : 2,835mol
remains completely consumed
2,14-1,89=0,25mol
A) Al
B)
C)
Answer:
+60.54 kJ/mol
Explanation:
The enthalpy of formation of a compound is the sum of the enthalpies of the formation of its constituents and the bond of them. To form a compound, energy must be lost, so, they're negative.
For SF4, the enthalpy is formed by the energy of one S, two F, and 4 S-F bond (Hb):
H = - (278.8 + 4*79.0 + 4*Hb)
-775 = -(594.8 + 4Hb)
594.8 + 4Hb = 775
4Hb = 180.2
Hb = +45.05 kJ/mol
For SF6, the enthalpy is formed by the energy of one S, six F, and 6 S--F bonds (Hb):
H = -(278.8 + 6*79.0 + 6*Hb)
-1209 = -(752.8 + 6Hb)
752.8 + 6Hb = 1209
6Hb = 456.2
Hb = +76.03 kJ/mol
Thus, the energy of S--F bond must be the average of these two:
(45.05 + 76.03)/2 = +60.54 kJ/mol
7 valence electrons in an atom
Answer:
(b) Tincture of iodine is made by dissolving iodine in alcohol
The answer is NO. It can not be a compound it is an element.
In a component mixture it can be separated physically way from the other.
In element it can be only separated by a way of destroying the compound itself by chemical reaction.
