Answer:
0.086
Explanation:
A 5.2 molal aqueous solution of methyl alcohol indicates that 5.2 moles of methyl alcohol are present in 1 kilogram (or 1000 g) of water. Water has a molecular weight of 18 g/mol.
(100g)/18g/mol=55.56 mol
5.2 mol/(5.2mol+55.56 mol)=0.086
This problem is providing two reduction-oxidation (redox) reactions in which the oxidized and reduced species can be identified by firstly setting the oxidation number of each element:
Reaction 1: 2K⁺I⁻ + H₂⁺O₂⁻ ⇒2K⁺O⁻²H⁺ + I₂⁰
Reaction 2: Cl₂⁰ + H₂⁰ ⇒ 2H⁺CI⁻
Next, we can see that iodine is being oxidized and oxygen reduced in reaction #1 and chlorine is being reduced and hydrogen oxidized in reaction #2 because the oxidized species increase the oxidation number whereas the reduced ones decrease it.
In such a way, the correct choice is C.
Learn more:
1. B
The positive charge in water is provided by hydrogen, and gold provides the same charge. However, gold is not more reactive than hydrogen so it can not replace it in the compound.
2. In order to balance the equation, you must sure there are equal moles of each element on the left and right side of the equation:
2C₂H₆ + 7O₂ → 4CO₂ + ₆H₂O
3. The number of moles of sodium atoms on the left of the equation must be equal to the number of moles of sodium atoms on the right, as per the law of conservation of mass. The answer is B.
4. C.
A synthesis reaction usually results from single displacement because some element or compound is produced in its pure form
5. B.
The gas being produced is being synthesized.
Answer:
A. a system that can be affected by the outside environment, by an exchange of matter or energy
The factor that does not influence stream velocity is DISCHARGE.
Stream velocity refers to the speed with which the water in a stream is flowing. The factors which affect stream velocity include channel size, channel shape, turbulent flow and gradient.
