Oxidation number is charge of element in compound. Can be neutral, positive or negative.
Oxygen in dichromate has oxidation number -2, becauce there are seven oxygens, net oxidation number of oxygen is -14.
2·x(oxidation number of Cr) + 7· (-2) = -2 2x= +12
x= +6, oxidation number of one chromium is +6.
Answer:
Explanation:
In one of the process, energy is built up from scratch, in the other one, energy is liberated for use by an organism or body.
The first process deals with a metabolic reaction in which energy is liberated:
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy
In the above process, energy is liberated when glucose combines with oxygen. The waste products are carbon dioxide and water. This process liberates heat energy which can be used to do work.
In the reverse process:
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
This process stores energy in carbon chains as chemical energy. It is this energy that is released in the first process.
Therefore, we can see that the first process liberates energy and the reverse process stores energy.
Answer:
330 mL of (NH₄)₂SO₄ are needed
Explanation:
First of all, we determine the reaction:
(NH₄)₂SO₄ + 2NaOH → 2NH₃ + 2H₂O + Na₂SO₄
We determine the moles of base:
(First, we convert the volume from mL to L) → 62.6 mL . 1L/1000 mL = 0.0626L
Molarity . volume (L) = 2.31 mol/L . 0.0626 L = 0.144 moles
Ratio is 2:1. Therefore we make a rule of three:
2 moles of hydroxide react with 1 mol of sulfate
Then, 0.144 moles of NaOH must react with (0.144 .1) /2 = 0.072 moles
If we want to determine the volume → Moles / Molarity
0.072 mol / 0.218 mol/L = 0.330 L
We convert from L to mL → 0.330L . 1000 mL/1L = 330 mL
Answer:
Carbon
Explanation:
Micronutrients include elements or groups needed by the body in order to survive. These elements or groups include vitamins and minerals. Micronutrients can be divided into four categories:
1. water-soluble vitamins
2. Fat-soluble vitamins
3. Macrominerals
4. Trace minerals