Answer: 
Explanation:
Electron gain enthalpy is defined as energy released on addition of electron to an isolated gaseous atom.
The amount of energy released will be maximum when the tendency to attract electrons is maximum. As flourine has atomic number of 9 and has electronic configuration of 2,7. It can readily gain 1 electron to attain stable noble gas configuration and hence liberates maximum energy.
4Al(s) + 3O2(g) --> 2Al2O3(s) This is the balanced.
From the equation:
4 moles of Al required 3 moles of O2 to produce 2 moles of Al2O3
3 moles of O2 reacted with 4 moles of Al to produce 2 moles of Al2O3
1 mole of O2 reacted with 4/3 moles of Al to produce 2/3 moles of Al2O3 (Divide by 3)
4.5 moles of O2 reacted with (4/3 *4.5) moles of Al to produce (2/3*4.5) moles of Al2O3
4.5 moles of O2 reacted with 6moles of Al to produce 3moles of Al2O3
(3) is the answer. 6 mol of Al.
Answer: The final pressure is 34.48kPa
Initial Pressure P1 = 55.16kPa
Initial Volume V1 = 0.500L
Final Pressure P2 = ?
Final Volume V2 = 0.800L
Boyle's law P1V1 = P2 V2
P2 = P1V1/V2
P2 = 55.16*0.5/0.8
P2 = 34.48kPa
Answer:
Zn+2HCl→ZnCl2+H2
Explanation:
Hydrogen gas is prepared in the laboratory by reacting dilute HCl with granulated zinc.
The kind of thermochemical equation represented below
that is
CaO(s) + H2O (l) = Ca(OH)2 (s) +65.2 kj
is exothermic ( answer B)
This is because its heat energy has a + sign meaning that heat is released by the reaction above.