Answer:
C
Explanation:
If the enthalpy change (i.e. Δ<em>H</em>) of a reaction is negative, then the reaction releases heat and is hence exothermic.
Hence, our answer is C.
Conversely, if Δ<em>H</em> is positive, the reaction absorbs heat and is endothermic.
Δ<em>H</em> tells us nothing about the speed of the reaction.
While Δ<em>H</em> influences free-energy change (Δ<em>G</em> = Δ<em>H</em> - <em>T</em>Δ<em>S</em>), we cannot predict the sign of Δ<em>G</em> given only Δ<em>H </em>(recall that a reaction is spontaneous if Δ<em>G</em> < 0).
The equation in this problem is: 2Pb(NO3)2(s) --> 2PbO(s)
+ 4NO2(g) + O2(g)
And the question is what the pressure in the cylinder is
after decomposition and cooling to a temperature of 300 K.
Solution:
Moles of Pb (NO3)2 = 3.31/331 = 0.0100
2 moles of Pb (NO3)2 will decay to mold 4 moles of NO2 and 1 mole of O2. So
0.0100 moles of Pb (NO3)2 will form 0.02 moles of NO2 and 0.00500 moles of
O2
Then use the formula: PV = nRT.
P = (0.02 + 0.005) * 0.082 * 300 / 1.62
= 0.380 atm
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I believe it's alkali metals and alkaline earth metals.
Answer:
Atoms can gain, lose, or share electrons during a chemical change. Chemical changes do not affect the nucleus of an atom. For this reason, an atom has the ability to retain its properties or identity even if the number of electrons is different. Therefore, the atom's identity won't change.
Explanation:
Answer:
In physics and chemistry, ionization energy or ionisation energy, is the minimum amount of energy required to remove the most loosely bound electron of an isolated neutral gaseous atom or molecule.
I hoped this helped :D
Explanation: