Unit 1 - Lecture 3 Topic 1

Question 1

What makes up a textile fibre?

Answer 1

All fibres are made of polymers. Thousands of molecules are covalently bonded together in long chains.

Question 2

Molecule:

Answer 2

A collection of atoms joined together.

Question 3

Atom:

Answer 3

Consists of a dense central nucleus surrounded by a cloud of negatively charged electrons.

Question 4

Covalent Bonding:

Answer 4

The most common type of bonding of atoms to form molecules that make up textiles. Covalent bonds are the strongest bonds that can form between atoms/molecules. Electrons are shared between atoms. The number of bonds an atom can form depends on the number of electrons needed to form a full valence shell

Question 5

What common atoms are present in textiles?

Answer 5

Carbon, oxygen and hydrogen are most common, with nitrogen and sulphuric also present.

Question 6

Double Bonds:

Answer 6

More easily broken and reactive than single bonds.

Question 7

Benzene:

Answer 7

A six-carbon ring with alternating double and single bonds that make it very stable.

Question 8

Polarity:

Answer 8

Electrons in a covalent bond are not always equally shared; some atoms are more electronegative than others. A polar molecule is where one atom has a slightly negative charge and the other atom has a slightly positive charge (eg, water).

Question 9

Polarity:

Answer 9

Electrons in a covalent bond are not always equally shared; some atoms are more electronegative than others. A polar molecule is where one atom has a slightly negative charge and the other atom has a slightly positive charge (eg, water).

Question 10

What are the common electronegative atoms in HECOL 170?

Answer 10

Oxygen and nitrogen.

Question 11

What are the common neutral atoms in HECOL 170?

Answer 11

Carbon and hydrogen.

Question 12

What happens when oxygen or nitrogen is bonded to carbon or hydrogen?

Answer 12

Electrons pull away from the carbon or hydrogen because oxygen and nitrogen are more electronegative.

Question 13

Hydrogen Bonds:

Answer 13

When a strong electrostatic attraction forms between the negative end of a polar molecule (O or N) and with the positive end of a polar molecule (H), this is known as a hydrogen bond. A hydrogen bond is depicted by a dashed line.

Question 14

Ionic Bonds:

Answer 14

Forms between two oppositely charged ions – some atoms lose an electron & some gain an electron. Sodium chloride (NaCl) (table salt) is a common example of ionic bonding.

Question 15

Ionic Bonds:

Answer 15

Forms between two oppositely charged ions – some atoms lose an electron & some gain an electron. Sodium chloride (NaCl) (table salt) is a common example of ionic bonding.

Question 16

Van der Waals forces:

Answer 16

Electrostatic bonds between atoms or molecules that result from short-lived asymmetric charge distributions in atoms & molecules. These are very weak forces that become stronger as atoms/molecules are packed more closely together. Textile polymers can be very large so van der Waals forces are very important.

Question 17

What are the types of intramolecular bonding?

Answer 17

Covalent bonding and ionic bonding.

Question 18

Van der Waals forces:

Answer 18

Electrostatic bonds between atoms or molecules that result from short-lived asymmetric charge distributions in atoms & molecules. They are very weak forces that become stronger as atoms/molecules are packed more closely together. Textile polymers can be very large so van der Waals forces are very important.

Question 19

What are the types of intermolecular bonding?

Answer 19

Hydrogen bonding, Van der Waals bonding, and in some cases, ionic and covalent bonds as well.