Hey there !
<span>Convert Joule to KJ :
</span>
1 j ---------------- 0.001 kj
53.69 j ----------- Kj
Kj = 53.69 * 0.001
=> 0.05369 Kj
T = ΔH / <span>ΔS
T = 49.09 / 0.05369
T = 914.32ºC</span>
Explanation:
Sodium has atomic number of 11 and its electronic configuration is given by:
![[Na]=1s^22s^22p^63s^1](https://tex.z-dn.net/?f=%5BNa%5D%3D1s%5E22s%5E22p%5E63s%5E1)
The nearest stable electronic configuration to sodium is of the neon. So, in order to attain stability of noble gas it will loose its single electron.

![[Na^+]=1s^22s^22p^63s^0](https://tex.z-dn.net/?f=%5BNa%5E%2B%5D%3D1s%5E22s%5E22p%5E63s%5E0)
Sodium has single valency that is 1.
Let nbe the valency of the ion 'X'
By criss-cross method, the oxidation state of the ions gets exchanged and they form the subscripts of the other ions. This results in the formation of a neutral compound.

So, the formulas for all the possible compounds that sodium can form with the other ions will be:

Answer:
[Co(NH₃)₄(H₂O)₂]³⁺: coordination number = 6.
[Cr(EDTA)]⁻: coordination number = 6.
[Pt(NH₃)₄]²⁺: coordination number = 4.
Na[Au(Cl)₂]: coordination number = 2.
Explanation:
In this complex, Co is bonded with 4 molecules of NH₃ (with 4 coordinate bonds, one bond for each molecule) and 2 molecules of H₂O (with 2 coordinate bonds, one bond for each molecule) forming the complex with 6 coordinate bonds.
∴ coordination number = 6.
In this complex, Cr is bonded with 1 molecules of EDTA (with 6 coordinate bonds, 4 O atoms and 2 N atoms in EDTA molecule).
∴ coordination number = 6.
In this complex, Pt is bonded with 4 molecules of NH₃ (with 4 coordinate bonds, one bond for each molecule).
coordination number = 4.
In this complex, Au is bonded with 2 atoms of Cl (with 2 coordinate bonds, one bond for each atom).
coordination number = 2.
<span>The pressure of nitrogen in atmospheres of a sample that is at 745 mmHg-
n2= .780 atm because
78 (from the 78%)
78/100=0.78.</span>
28.01 g/mol
hope that helped