Answer:
C
Explanation:
The law proves C. For examples no matter how water you have it will always have a 1:2 ratio of oxygen to hydrogen. :)
Answer:
Mass = 5.56 g
Explanation:
Given data:
Mass of Cl₂ = 4.45 g
Mass of NaCl produced = ?
Solution:
Chemical equation:
2Cl₂ + 4NaOH → 3NaCl + NaClO₂ + 2H₂O
Number of moles of Cl₂:
Number of moles = mass/molar mass
Number of moles = 4.45 g/ 71 g/mol
Number of moles = 0.063 mol
Now we will compare the moles of Cl₂ with NaCl.
Cl₂ : NaCl
2 : 3
0.063 : 3/2×0.063 =0.095 mol
Mass of NaCl:
Mass = number of moles × molar mass
Mass = 0.095 mol × 58.5 g/mol
Mass = 5.56 g
Answer:
D. Ni²⁺
Explanation:
We know at once that the answer cannot be A or C, because Ni and Cu are already in their lowest oxidation states.
The correct answer must be either B or D.
An electrolytic cell is the opposite of a galvanic cell. In the former, the reaction proceeds spontaneously. In the latter, you must force the reaction to occur.
One strategy to solve this problem is:
- Look up the standard reduction potentials for the half reaction·
- Figure out the spontaneous direction.
- Write the equation in the reverse direction.
1. Standard reduction potentials
E°/V
Cu²⁺ + 2e⁻ ⟶ Cu; 0.3419
Ni²⁺ + 2e⁻ ⟶ Ni; -0.257
2. Galvanic Cell
We reverse the direction of the more negative half cell and add.
<u>E°/V
</u>
Ni ⟶ Ni²⁺ + 2e⁻; 0.257
<u>Cu²⁺ + 2e⁻ ⟶ Cu; </u> 0.3419
Ni + Cu²⁺ ⟶ Cu + Ni²⁺; 0.599
This is the spontaneous direction.
Cu²⁺ is reduced to Cu.
3. Electrochemical cell
<u>E°/V</u>
Ni²⁺ + 2e⁻ ⟶ Ni; -0.257
<u>Cu ⟶ Cu²⁺ + 2e⁻; </u> <u>-0.3419</u>
Cu + Ni²⁺ ⟶ Ni + Cu²⁺; -0.599
This is the non-spontaneous direction.
Ni²⁺ is reduced to Ni in the electrolytic cell.
The 2.5 x 10²¹ molecules of CH₃OH have 0.00415 moles.
<h3>What is the mole concept?</h3>
- The Mole concept is used to express the amount of substance conveniently.
- A mole is defined as the amount of substance that contains exactly 6.022 x 10²³ elementary particles of the given substance. Here, elementary particles refer to atoms, molecules, or ions.
- This fixed number 6.022 x 10²³ is known as Avogadro Number and is denoted by
<h3>How to calculate the number of moles?</h3>
The number of moles is given by
When given mass = molar mass of a substance, then no of moles is equal to 1 which is equivalent to 6.022 x 10²³.
We also know,
1 mole has 6.022 x 10²³ molecules of CH₃OH
According to the mole concept,
6.022 x 10²³ molecules of CH₃OH is equal to 1 mole
2.5 x 10²¹molecules of CH₃OH is equal to 
moles
Thus, 2.5 x 10²¹molecules of CH₃OH are equal to 4.15 x 10⁻³ moles or 0.00415 moles
Learn more about the mole concept:
brainly.com/question/1427235
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