Answer: 4 valence electrons, Silicon, Si, 14, 28.0855, 14
Explanation:
1) 1 molecules
2) 2 oxygen atoms
3)2 moles of Al2O3 are formed
4)4:3
Answer:
2.63*10^23
Explanation:
1 mol rhodium = 102.91
44.8g/1 mol * 1 mol/ 102.91mol * 6.022*10^23/1 mol =
2.63*10^23
Hello!
We know that by the Law of Avogrado, for each mole of substance we have 6.02 * 10²³ atoms, if:
The molar mass of water (H2O)
H = 2 * (1u) = 2u
O = 1 * (16u) = 16u
---------------------------
The molar mass of H2O = 2 + 16 = 18 g / mol
If:
1 mol we have 6.02 * 10²³ atoms
1 mole of H2O we have 18 g
Then we have:
18 g ------------- 6.02 * 10²³ atoms
5 g -------------- x
I Hope this helps, greetings ... DexteR! =)
Answer:
ΔH = -470.4kJ
Explanation:
It is possible to sum 2 or more reactions to obtain the ΔH of the reaction you want to study (Hess's law). Using the reactions:
1. CaC2(s) + 2H2O(l) → C2H2(g) + Ca(OH)2(s)ΔH = −414kJ
2. 6C2H2(g) + 3CO2(g) + 4H2O(g) → 5CH2CHCO2H(g)ΔH = 132kJ
6 times the reaction 1.
6CaC2(s) + 12H2O(l) → 6C2H2(g) + 6Ca(OH)2(s)ΔH = −414kJ*6 = -2484kJ
This reaction + 2:
6CaC2(s) + 3CO2(g) + 16H2O(l) → + 6Ca(OH)2(s) + 5CH2CHCO2H(g) ΔH = -2484kJ + 132kJ = -2352kJ
As we want to calculate the net change enthalpy in the formation of just 1 mole of acrylic acid we need to divide this last reaction in 5:
6/5CaC2(s) + 3/5CO2(g) + 16/5H2O(l) → + 6/5Ca(OH)2(s) + CH2CHCO2H(g) ΔH = -2352kJ / 5
<h3>ΔH = -470.4kJ</h3>
