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3 years ago

What’s the difference between a pi bond and a sigma bond?

1 answer:

8 0

A triple bond is one sigma and two pi bonds. A sigma bond is your basic head-on covalent bond, with the bond in line with the bonding orbitals. You can only ever have one sigma bond between any two atoms. A pi bond is a covalent bond between orbitals perpendicular to the bond direction, usually p-orbitals (never s).

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Iron(III) oxide and hydrogen react to form iron and water, like this: (s)(g)(s)(g) At a certain temperature, a chemist finds tha

stepan [7]

The question is incomplete, here is the complete question:

Iron(III) oxide and hydrogen react to form iron and water, like this:

$Fe_2O_3(s)+3H_2(g)\rightarrow 2Fe(s)+3H_2O(g)$

At a certain temperature, a chemist finds that a 5.4 L reaction vessel containing a mixture of iron(III) oxide, hydrogen, iron, and water at equilibrium has the following composition:

Compound Amount

$Fe_2O_3$ 3.54 g

$H_2$ 3.63 g

Fe 2.37 g

$H_2O$ 2.13 g

Calculate the value of the equilibrium constant for this reaction. Round your answer to 2 significant digits

Answer: The value of equilibrium constant for the given reaction is $2.8\times 10^{-4}$

Explanation:

To calculate the molarity of solution, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Mass of solute}}{\text{Molar mass of solute}\times \text{Volume of solution (in L)}}$

For hydrogen gas:

Given mass of hydrogen gas = 3.63 g

Molar mass of hydrogen gas = 2 g/mol

Volume of solution = 5.4 L

Putting values in above equation, we get:

$\text{Molarity of hydrogen gas}=\frac{3.63}{2\times 5.4}\\\\\text{Molarity of hydrogen gas}=0.336M$

For water:

Given mass of water = 2.13 g

Molar mass of water = 18 g/mol

Volume of solution = 5.4 L

Putting values in above equation, we get:

$\text{Molarity of water}=\frac{2.13}{18\times 5.4}\\\\\text{Molarity of water}=0.0219M$

The given chemical equation follows:

$Fe_2O_3(s)+3H_2(g)\rightarrow 2Fe(s)+3H_2O(g)$

The expression of $K_c$ for above equation follows:

$K_c=\frac{[H_2O]^3}{[H_2]^3}$

The concentration of pure solids and pure liquids are taken as 1 in equilibrium constant expression. So, the concentration of iron and iron (III) oxide is not present in equilibrium constant expression.

Putting values in above equation, we get:

$K_c=\frac{(0.0219)^3}{(0.336)^3}\\\\K_c=2.77\times 10^{-4}$

Hence, the value of equilibrium constant for the given reaction is $2.8\times 10^{-4}$

7 0

3 years ago

Q 16.1: Select the first step in the Wittig reaction. A : The alkyltriphenylphosphonium halide is deprotonated by a base to make

Dennis_Churaev [7]

Answer:

The phosphorus ylide reacts with the aldehyde or ketone to make an oxaphosphetane.

Explanation:

The Wittig reaction is a reaction that occurs between a phosphorus ylide and an aldehyde or ketone. The final products are an alkene and triphenyl phosphine oxide.

The first step in the reaction is the attack of the phosphorus ylide on the aldehyde or ketone. This is followed by attack of oxygen on phosphorus to form a [2+2] cycloaddition product (oxaphosphetane) which decomposes to form the alkene and triphenylphosphine oxide.

6 0

3 years ago

A system is in equilibrium when the rate of the forward reaction is _____ the rate of the reverse reaction.

NemiM [27]

Answer:

Option 4) equal to

Explanation

When having a reversible reaction, this reaction (or system) reaches the balnace, it is observed that relative quantitives for all compounds (this is, reactives and products), remain constant

The species concentration does not change over time, and; in the same way; there are no physical changes as time goes by

For example, for the following reaction :

aA + bB ⇔ cC + dD

Compounds A and B react to give products C and D. The two way arrows means that this systme has reached the balance (is in equilibrium)

3 0

4 years ago

Why is not used at nuclear plant as a soverce for electrical energy

nikitadnepr [17]

The biggest reason is radioactive wastes. Nuclear power generated radioactive wastes like Uranimum, plutonium and amercium that inhibits gene expression and causes cancer to the environment. Nuclear plants use to release these wastes into the oceans, and it causes fishes to exhibit gender change, 3 eyes, 2 tails etc. The impact on human shows signs of serious blood, liver and lung cancers.

There are currently no way to get rid of these wastes as they take hundred thousands of years to decompose.

Another reason is they cause a small amount of green gas emission. Releases CO2 to the sky. They exhibit radioactive gas emission as well (causes cancer) .

7 0

3 years ago

Use the atom builder interactive to identify each nucleus. Two protons represented as purple spheres and one neutron represented

aleksandr82 [10.1K]

Answer:

$\frac{3}{2}He$

$\frac{6}{2} He$

$\frac{7}{4}Be$

$\frac{3}{1} H$

$\frac{6}{4}Be$

$\frac{7}{3} Li$

Explanation:

In the first nucleus we are told that there are two protons and one neutron. Let us remember that the mass number = number of protons + number of neutrons.

This implies that, for the first specie the mass number is 3, for the second specie the mass number is 6 and the third specie has a mass number of 7 and so on. The mass number is indicated as a superscript.

The atomic number is the number of protons in the nucleus of the atom and helps us to identify the atom. It is always written as a subscript as shown.

5 0

3 years ago