At 4 °C, the clusters start forming. The molecules are still slowing down and coming closer together, but the formation of clusters makes the molecules be further apart. Thus, the density of water is a maximum at 4 °C.
First we will calculate free energy change:
ΔG₀ = ΔH₀ - (T * ΔS₀)
= - 793 kJ - (298 * - 0.319 kJ/K) = - 698 kJ
We know the relation between free energy change and cell potential is:
ΔG₀ = - n F E⁰ where
F = Faraday's constant = 96485 C/mol
n = 2 (given by equation that the electrons involved is 2)
ΔG₀ = - 2 x 96485 x E⁰
- 698 kJ = - 2 x 96485 x E⁰
E⁰ = (698 x 1000) / (2 x 96485) = 3.62 volts
You have to calculate the oxidation estates of the atoms in each compound.
I will start with K2Cr2O7 because I believe that Cr is the best candidate to reduce its oxidation number in 3 units.
In K2Cr2O7:
- K has oxidation state of 1+, then K2 has a charge of 2* (1+) = 2+.
- O has oxidation state of 2*, then O7 has a charge of 7* (2-) = 14-.
That makes that Cr2 has charge of 14 - 2 = +12, so each Cr has +12/2 = +6 oxidation state.
In Cr2O3:
- O has oxidation state of 2-, then O3 has charge 3 * (2-) = - 6
- Then, Cr2 has charge 6+, and each Cr has charge 6+ / 2 = 3+.
So, we have seen that Cr reduced its oxidation state in 3 units, from 6+ to 3+.
Answer: Cr has a change in oxidation number of - 3.
Answer:
2M
Explanation:
M=mol/L
1. Find moles of CoCl2
mass of substance/molar mass = 130/129.833 = 1.001 mol
3. Substitute in molarity equation
M=(1.001/0.5)
M= around 2M
The volume : 8,526 quarts
<h3>Further explanation</h3>
Given
The density of whole milk = 1.04 g/ml
mass = 18.5 pounds
Required
The volume
Solution
Conversion of mass
1 pound = 453,592 g
18.5 pounds = 8391,45 g
Density formula:
.
Input the value :
V = m : ρ
V = 8391,45 g : 1.04 g/ml
V = 8068.7 ml
1 ml = 0,00105669 quarts
8068.7 ml =8,526 quarts