The heat of reaction : 50.6 kJ
<h3>Further explanation</h3>
Based on the principle of Hess's Law, the change in enthalpy of a reaction will be the same even though it is through several stages or ways
Reaction
N₂(g) + 2H₂(g) ⇒N₂H₄(l)
thermochemical data:
1. N₂H₄(l)+O₂(g)⇒N₂(g)+2H₂O(l) ΔH=-622.2 kJ
2. H₂(g)+1/2O₂(g)⇒H₂O(l) ΔH=-285.8 kJ
We arrange the position of the elements / compounds so that they correspond to the main reaction, and the enthalpy sign will also change
1. N₂(g)+H₂O(l) ⇒ N₂H₄(l)+O₂(g) ΔH=+622.2 kJ
2. H₂(g)+1/2O₂(g)⇒H₂O(l) ΔH=-285.8 kJ x 2 ⇒
2H₂(g)+O₂(g)⇒2H₂O(l) ΔH=-571.6 kJ
Add reaction 1 and reaction 2, and remove the same compound from different sides
1. N₂(g)+2H₂O(l) ⇒ N₂H₄(l)+O₂(g) ΔH=+622.2 kJ
2.2H₂(g)+O₂(g)⇒2H₂O(l) ΔH=-571.6 kJ
-------------------------------------------------------------------- +
N₂(g) + 2H₂(g) ⇒N₂H₄(l) ΔH=50.6 kJ
the cathode is where reduction occurs!
1 mol of any particles has 6.02 * 10 ²³ particles.
If we look at 1 NH3 (1 mol NH3 or 1 molecule NH3), we can see that 1 molecule NH3 has 1 atom of N and 3 atoms of H; also 1 mole of NH3 has 1 mole of N atoms and 3 moles of H atoms.
So, 1 mol of NH3 has 1 mol of N atoms,
and 2.79 mol NH3 have 2.79 mol of N atoms.
2.79 mol of N atoms* 6.02 * 10 ²³ N atoms/ 1 mol N atoms = 1.68*10²⁴ N-atoms
Answer is 1.68*10²⁴ N-atoms.
The crest is cover distance. <span>The </span>speed<span> of a wave indicate how fast wave is moving. </span>T<span>he speed is the distance traveled by a crest in a given interval of time. Greater distance in same amount of time means wave travel faster.
speed of wave = distance/time.
speed of wave = 0,2 m </span>÷ 0,2 s = 1 m/s.
Based on the periodic table, the element mendeleev called eka-manganese is now called technetium. Technetium<span> is a silvery-gray metal that tarnishes slowly in moist air. Hope this answers the question. Have a nice day. Feel free to ask more questions.</span>
