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3 years ago

Write an ionic half equation for the formation of hydrogen during this electrolysis

Chemistry

1 answer:

Alexxandr [17]3 years ago

6 0

Answer:

A half-equation shows you what happens at one of the electrodes during electrolysis. Electrons are shown as e-. A half-equation is balanced by adding, or taking away, a number of electrons equal to the total number of charges on the ions in the equation.

When positive metal ions (cations) arrive at the negative electrode (the cathode), they gain electrons to form neutral metal atoms. This is called reduction. For example:

Pb2+ + 2e- → Pb

When negative non-metal ions (anions) arrive at the positive electrode (the anode), they lose electrons to form neutral atoms or molecules. This is called oxidation. For example:

2Br- → Br2 + 2e-

Writing half equations

Cations go to the cathode. They need to gain enough electrons to make them neutral. So an Al3+ ion needs to gain three electrons:

Al3+ + 3e- → Al

Half-equations for non-metal anions are more difficult to balance. For example, chloride ions make chlorine gas. Most non-metal elements formed in electrolysis are diatomic molecules (eg Cl2). For example:

Cl- → Cl2

Add in two electrons to balance the charge so that both sides have the same charge. The two electrons need to go on the right-hand side, so that both sides have an overall charge of -2. For example:

2Cl- → Cl2 + 2e-

You might be interested in

A chemist needs 1.25 moles of sugar to dissolve in 1 liter of water how many grams of sugar needed

sdas [7]

Answer:

The mass of sugar used is 427.5 grams.

Explanation:

The formula of common sugar is $\mathrm{C_{12}H_{22}O_{11}}$ .

Its molar mass of molecule is 342 grams per mole.

The number of moles of sugar used is equal to '1.25'

$\mathbf{Mole=\frac{Mass \ given \ in \ grams}{Molar \ mass \ of \ molecule \ in \ grams}}$

$\textrm{Mass in grams}=\textrm{Mole} \times \textrm{Molar mass of molecule in grams}$

$\textrm{Mass in grams}= 1.25\times342$

$\mathbf{Mass \ in \ grams=427.5 g}$

(NOTE : You can calculate molar mass by adding the mass of all the atoms present in the atom.

Mass of Oxygen (O) = 16 ; Total number of Oxygen atoms present = 11

Mass of Hydrogen (H) =1 ; Total number of Hydrogen Atoms present = 22

Mass of Carbon (C) = 12 ; Total number of Carbon atoms present = 12

Total mass of molecule = 12 × 12 + 1 × 22 + 16 × 11 = 342)

4 0

3 years ago

6. Write the ICE chart for the reaction of 32.0 g of sulfur and 71.0 g of chlorine: S8 + 4 Cl24S2Cl2 After completing the chart

Marianna [84]

Answer:

ICE Table Figure

a. 67.37 g $S_2Cl_2$

b. 35.62 g $Cl_2$

c. 58.61 g $S_2Cl_2$

Explanation:

For the ICE table we have to keep in mind that we have 4 moles of $Cl_2$ and 1 mol of $S_8$ and the reactives are consumed, so for $Cl_2$ we will have -4X and for $S_8$ we will have -X. Follow the same logic we will have -4X for $S_2Cl_2$ .

a. Mass of the product

Molar mass of $S_8$ = 256.52 g/mol

Molar mass of $Cl_2$ =70.9 g/mol

Molar mass of $S_2Cl_2$ =135.03 g/mol

We have to find the limiting reagent in the reaction:

$S_8+4Cl_2->4S_2Cl_2$

$\frac{32}{256.52}=0.124molS_8$

$\frac{71}{70.9}=1 molCl_2$

Divide by the coefficients in the balanced reaction:

$\frac{0.124}{1}=0.124mol$

$\frac{1}{4}=0.25 mol$

The limiting reagent would be $S_8$

Now is posible to calculate the amount of $S_2Cl_2$ produced:

$0.124molS_8\frac{4molS_2Cl_2}{1 molS_8}\frac{135.03gS_2Cl_2}{1 molS_2Cl_2}=67.37gS_2Cl_2$

b. Mass in excess

$0.124molS_8\frac{4molCl_2}{1 molS_8}\frac{70.9gCl_2}{1 molCl_2}=35.38gCl_2$

$Excess\hspace{0.1cm}=\hspace{0.1cm}71gCl_2-35.38gCl_2=35.62 gCl_2$

C. 87%Yield

$67.37gS_2Cl_2\frac{87}{100}=58.61gS_2Cl_2$

5 0

4 years ago

What is the molar mass of a gas with a density of 3.50 g/L at a

Kruka [31]

Answer:

104 g/mol

Explanation:

Use the ideal gas equation:

$pV=nRT$

Where:

p is pressure: 0.950atm
V is volume: unknown
n is number of moles: unknown
R is the universal constat of gases: 0.08206 atm.liter/ (K.mol)
T is the absolute temperature: 345K

Use the molar mass of the gas to include the density in the formula:

molar mass = mass in grams / number of moles

⇒ mass in grams = number of moles × molar mass

density = mass in grams / volume

⇒ density = number of moles × molar mass / volume

density = (n/V) × molar mass

⇒ n/V = density / molar mass

Clear n/V from the gas ideal equation and subsittute with density/molar mass:

n/V = p/(RT)

density / molar mass = n/V

density/molar mass = p/(RT)

molar mass = density × RT / p

Now you can subsitute the data:

molar mass = (3.50g/liter) × 0.08206 atm.liter/(K.mol) × 345K / 0.950 atm

molar mass = 104.3 g/mol

Round to the nearest whole number: 104g/mol ← answer

3 0

3 years ago

Balance the single replacement chemical reaction.

OLEGan [10]

Answer:

Option c. 2Kl + Cl2 —> 2KCl + l2

Explanation:

A balanced equation must have the same number of atoms on the reactants side and the products side. This do the fact of the postulation by the mass conservation principle that says: Atoms can neither be broken nor destroyed but can be arranged. The atoms on the left side for each element are equal. Thus, C presents a balanced equation.

3 0

4 years ago

3. describe natural sources of radiation. infer some of the dangers that radiation can impose.

maxonik [38]

Answer:

All of us are exposed to radiation every day, from natural sources such as minerals in the ground, and man-made sources such as medical x-rays. According to the National Council on Radiation Protection and Measurements (NCRP), the average annual radiation dose per person in the U.S. is 6.2 millisieverts (620 millirem).

Explanation:

4 0

3 years ago