Carbon has a tendency to form covalent bonds.
1) Calculate the number of moles of O2 (g) in 300 cm^3 of gas at 298 k and 1 atm
Ideal gas equation: pV = nRT => n = pV / RT
R = 0.0821 atm*liter/K*mol
V = 300 cm^3 = 0.300 liter
T = 298 K
p = 1 atm
=> n = 1 atm * 0.300 liter / [ (0.0821 atm*liter /K*mol) * 298K] = 0.01226 mol
2) The reaction of a metal with O2(g) to form an ionic compound (with O2- ions) is of the type
X (+) + O2 (g) ---> X2O or
2 X(2+) + O2(g) ----> X2O2 = 2XO or
4X(3+) + 3O2(g) ---> 2X2O3
In the first case, 1 mol of metal react with 1 mol of O2(g); in the second case, 2 moles of metal react with 1 mol of O2(g); in the third, 4 moles of X react with 3 moles of O2(g)
So, lets probe those 3 cases.
3) Case 1: 1 mol of metal X / 1 mol O2(g) = x moles / 0.01226 mol
=> x = 0.01226 moles of metal X
Now you can calculate the atomic mass of the hypotethical metal:
1.15 grams / 0.01226 mol = 93.8 g / mol
That does not correspond to any of the metal with valence 1+
So, now probe the case 2.
4) Case 2:
2moles X metal / 1 mol O2(g) = x / 0.01226 mol
=> x = 2 * 0.01226 = 0.02452 mol
And the atomic mass of the metal is: 1.15 g / 0.02452 mol = 46.9 g/mol
That is similar to the atomic mass of titanium which is 47.9 g / mol and whose valece is 2+.
4) Case 3
4 mol meta X / 3 mol O2 = x / 0.01226 => x = 0.01226 * 4 / 3 = 0.01635
atomic mass = 1.15 g / 0.01635 mol = 70.33 g/mol
That does not correspond to any metal.
Conclusion: the identity of the metallic element could be titanium.
The correct answer is H2SO3 I took the assignment already
Answer: The concentration of hydrogen ion in the given solution is 
.
Explanation:
pOH of a solution is the negative logarithm of concentration of hydroxide ions.
Hence, if ![[OH^{-}]](https://tex.z-dn.net/?f=%5BOH%5E%7B-%7D%5D)
is 
then its pOH value is calculated as follows.
![pOH = -log [OH^{-}]\\= -log (3.5 \times 10^{-5})\\= 4.45](https://tex.z-dn.net/?f=pOH%20%3D%20-log%20%5BOH%5E%7B-%7D%5D%5C%5C%3D%20-log%20%283.5%20%5Ctimes%2010%5E%7B-5%7D%29%5C%5C%3D%204.45)
Now, the relation between pH and pOH is as follows.
pH + pOH = 14
pH + 4.45 = 14
pH = 14 - 4.45
= 9.55
And, pH is the negative logarithm of concentration of hydrogen ions. Hence, ![[H^{+}]](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D)
is calculated as follows.
![pH = -log [H^{+}]\\9.55 = -log [H^{+}]\\H^{+} = 2.81 \times 10^{-10}](https://tex.z-dn.net/?f=pH%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D%5C%5C9.55%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D%5C%5CH%5E%7B%2B%7D%20%3D%202.81%20%5Ctimes%2010%5E%7B-10%7D)
Thus, we can conclude that the concentration of hydrogen ion in the given solution is .
