What is the Bonding in Ethene?

S6-SA4-0215

Grade Level:

Class 10

AI/ML, Physics, Biotechnology, Space Technology, Chemistry, Engineering, Medicine

Definition

What is it?

The bonding in ethene refers to how its carbon and hydrogen atoms are connected to each other. Ethene (C2H4) has a special type of bond between its two carbon atoms, called a double covalent bond, and single covalent bonds with hydrogen atoms.

Simple Example

Quick Example

Imagine you and your best friend are sharing a plate of samosas. If you each contribute one samosa, that's like a single bond. But if you both contribute two samosas each to share, that's like a double bond – a stronger, more committed sharing! In ethene, the two carbon atoms 'share' two pairs of electrons, making a double bond.

Worked Example

Step-by-Step

Let's figure out the bonding in Ethene (C2H4) step-by-step:
1. **Identify the atoms:** We have 2 Carbon (C) atoms and 4 Hydrogen (H) atoms.
2. **Recall valency:** Carbon has a valency of 4 (needs 4 bonds), and Hydrogen has a valency of 1 (needs 1 bond).
3. **Connect Carbon atoms:** First, connect the two Carbon atoms with a single bond. Each Carbon now has 3 valencies remaining.
4. **Attach Hydrogen atoms:** We have 4 Hydrogen atoms. Distribute them equally to the two Carbon atoms. Each Carbon gets 2 Hydrogen atoms, forming 2 single C-H bonds.
5. **Check valencies:** Now, each Carbon atom has formed 1 C-C bond and 2 C-H bonds, totaling 3 bonds. But Carbon needs 4 bonds.
6. **Form the double bond:** To satisfy Carbon's valency, the two Carbon atoms must share another pair of electrons, forming a second bond between them. So, the C-C bond becomes a double bond.
7. **Final check:** Each Carbon now has 2 bonds with the other Carbon and 2 bonds with Hydrogen atoms (2+2=4 bonds). Each Hydrogen has 1 bond with Carbon. All valencies are satisfied.
ANSWER: Ethene has one Carbon-Carbon double bond and four Carbon-Hydrogen single bonds.

Why It Matters

Understanding ethene's bonding is crucial for fields like Biotechnology and Medicine, as many organic molecules, including drugs, have similar structures. Chemical engineers use this knowledge to design processes for making plastics like polyethylene, which is found in many everyday items. It's fundamental to understanding how different substances react.

Common Mistakes

MISTAKE: Assuming all bonds in ethene are single bonds, like in ethane. | CORRECTION: Remember ethene is an 'alkene' and specifically has a carbon-carbon DOUBLE bond. This is its defining feature.

MISTAKE: Incorrectly counting the number of bonds for each carbon atom, leading to unsatisfied valency. | CORRECTION: Always ensure each carbon atom forms exactly four bonds (valency of 4) and each hydrogen atom forms exactly one bond (valency of 1).

MISTAKE: Drawing ethene as a linear molecule with carbons at the ends. | CORRECTION: Ethene is a planar molecule with the two carbon atoms centrally bonded and hydrogens attached symmetrically.

Practice Questions

Try It Yourself

QUESTION: How many single covalent bonds are present in an ethene molecule? | ANSWER: 4 (four C-H single bonds)

QUESTION: If an ethene molecule has one double bond, how many electron pairs are being shared between the two carbon atoms? | ANSWER: 2 electron pairs

QUESTION: Draw the electron dot structure (Lewis structure) for ethene, showing all valence electrons and bonds. | ANSWER: (Student should draw C=C with two H's attached to each C, showing 8 electrons around each C and 2 electrons around each H, using dots or lines for bonds.)

MCQ

Quick Quiz

Which of the following statements about the bonding in ethene is correct?

It has only single covalent bonds.

It has one carbon-carbon double bond and four carbon-hydrogen single bonds.

It has two carbon-carbon double bonds.

Each carbon atom forms five bonds.

The Correct Answer Is:

Ethene (C2H4) is characterized by a double bond between its two carbon atoms. To satisfy the valency of carbon (4), each carbon atom also forms single bonds with two hydrogen atoms. Therefore, it has one C=C double bond and four C-H single bonds.

Real World Connection

In the Real World

Ethene is a very important chemical in India and globally! It's used to make polyethylene, the plastic that makes up your water bottles, milk pouches, and many plastic bags. Farmers also use ethene gas to ripen fruits like mangoes and bananas faster, making sure they are ready for the market on time.

Key Vocabulary

Key Terms

COVALENT BOND: A chemical bond formed by the sharing of electron pairs between atoms. | DOUBLE BOND: A covalent bond involving two shared pairs of electrons between two atoms. | VALENCY: The combining capacity of an element, typically the number of bonds an atom can form. | HYDROCARBON: An organic compound consisting entirely of hydrogen and carbon.

What's Next

What to Learn Next

Great job understanding ethene's unique bonding! Next, you should explore 'What is the Bonding in Ethyne?' This will introduce you to triple bonds, which are even more fascinating and build directly on your knowledge of single and double bonds.