Answer:
-241.826 kJ·mol⁻¹; -146.9 J·K⁻¹mol⁻¹; 664.6 J·K⁻¹mol⁻¹; spontaneous
Explanation:
½O₂(g) + H₂(g) ⟶ H₂O(g)
ΔHf°/kJ·mol⁻¹: 0 0 -241.826
S°/J·K⁻¹mol⁻¹: 205.0 130.6 188.7
1. ΔᵣH
ΔᵣH = products -reactants = -241.826 -(0 + 0) = -241.826 kJ·mol⁻¹
2. ΔᵣS
ΔᵣS = products - reactants = 188.7 - (205.0 + 130.6) = 188.7 - 335.6 = -146.9 J·K⁻¹mol⁻¹
3. ΔS(univ)
4. Spontaneity
ΔG is negative, so the reaction is spontaneous.
3.16 X 10^-11 M is the [OH-] concentration when H3O+ = 1.40 *10^-4 M.
Explanation:
data given:
H30+= 1.40 X 10^-4 M\
Henderson Hasslebalch equation to calculate pH=
pH = -log10(H30+)
putting the values in the equation:
pH = -log 10(1.40 X 10^-4 M)
pH = 3.85
pH + pOH =14
pOH = 14 - 3.85
pOH = 10.15
The OH- concentration from the pOH by the equation:
pOH = -log10[OH-]
10.5= -log10[OH-]
[OH-] = 10^-10.5
[OH-] = 3.16 X 10^-11 is the concentration of OH ions when hydronium ion concentration is 1.40 *10^-4 M.
Answer:
Atom
Explanation:
atom: The basic unit of matter; the smallest unit of an element, having all the characteristics of that element; consists of negatively-charged electrons and a positively-charged center called a nucleus.
The Law of Conservation of Mass says that there can be no more or no less mass after a chemical reaction, so 24.4g+ 12.3 g has to equal the mass of Ca(OH)2
Answer:
Magnesium oxide
Explanation:
When magnesium reacts with oxygen, the magnesium atoms donate electrons to O2 molecules and thereby reduce the oxygen. Magnesium therefore acts as a reducing agent in this reaction. The O2 molecules, on the other hand, gain electrons from magnesium atoms and thereby oxidize the magnesium.
