Answer:
the molecules of water contracts when it is frozen
To analyze. Oml they won't let me add it unless I write more. Smh.
Answer:
2.63g
This means that every mole of water molecules will contain 2 moles of hydrogen and 1 mole of oxygen atoms.
To find the percent composition of hydrogen in water, use the molar mass of water and that of hydrogen
2×1.00794g/mol18.0153g/mol×100=11.19%
This means that every 100 g of water will contain a total of 11.19 g of hydrogen. Since your sample has a mass of 23.5 g, it follows that it will contain
23.5g water⋅11.19 g H100g water=2.63 g H
Here we have to get the residual concentration of Cu²⁺ in the reaction.
The residual concentration of [Cu²⁺] is 2.137×10⁸ m
The reaction between ammonia (NH₃) and CuSO₄ in ionic form is - Cu²⁺ + 4 NH₃ = [Cu(NH₃)₄]²⁺.
Thus 1 mole of Cu²⁺ will react with 4 moles of NH₃.
Now 6m NH₃ or 6 moles of ammonia will react with
= 1.5 moles of Cu²⁺.
Thus the Nernst equation of the reaction is
= E° +
log
.
Here the number of moles is 3, as 6 moles of ammonia will react with 1.5 moles of cu²⁺. and the standard reduction potential (E°) of Cu²⁺/Cu system is (+) 0.674V and the cell potential is 0.92V
On plugging the values in the equation, we get,
0.92 = 0.674 +
log[Cu²⁺]
Or, 0.029 log [Cu²⁺]= 0.246
Or, log [Cu²⁺] = 8.33
Or, [Cu²⁺] = 2.137×10⁸