Chapter 2 And 4 - Carbon And The Chemical Context Of Life

Question 1

Matter

Answer 1

Anything that takes up space and has mass

Question 2

Element

Answer 2

A substance that cannot be broken down to other substances by chemical reactions

Question 3

Compound

Answer 3

A substance consisting of two or more elements combined in a fixed ratio in

Question 4

Essential Elements

Answer 4

An element that an organism needs to live a healthy life and reproduce

Question 5

Trace elements

Answer 5

Elements required by elements in only minute qualities

Question 6

Atom

Answer 6

The smallest unit of matter that still retains the properties of an element

Question 7

Atomic Nucleus

Answer 7

Where protons and neutrons are packed at the centre of an atom. Protons give the nucleus a positive charge

Question 8

Electrons around nucleus

Answer 8

The rapidly moving electrons form a “cloud” of negative charge around the nucleus, and it is the attraction between opposite charges that keeps the nucleus electrons in the vicinity of the nucleus

Question 9

Atomic Number

Answer 9

Number of protons

Question 10

Mass number

Answer 10

Sum of neutrons and protons in the nucleus of an atom

Question 11

Isotopes

Answer 11

Different atomic forms of the same element

Question 12

Radioactive isotope

Answer 12

An isotope whose nucleus decays spontaneously, giving off particles and energy

Question 13

Energy

Answer 13

That capacity to cause change by doing work

Question 14

Potential energy

Answer 14

The energy that matter processes because of its location or structure

Question 15

Valence Electron

Answer 15

Electrons in the outermost shell

Question 16

Chemical Bonds

Answer 16

Attractions that hold atoms together

Question 17

Covalent Bonds

Answer 17

The sharing of a pair of valence electrons by two atoms

Question 18

Molecule

Answer 18

Two or more atoms held together by covalent bonds

Question 19

Single Bond

Answer 19

Shares one valence electron

Question 20

Double bond

Answer 20

Share two pairs of valence electrons

Question 21

Valence

Answer 21

An atoms bonding capacity

Question 22

Electronegativity

Answer 22

The attraction of a particular atom for the electrons of a covalent bond

Question 23

Nonpolar covalent bond

Answer 23

In a covalent bond, between two atoms of the same element, the electrons are shared equally because the two atoms have the same electronegativity

Question 24

Polar covalent bond

Answer 24

When an atom is bonded to a more electronegative atom, the electrons of the bond are not shared equally

Question 25

Electronegativity Scale

Answer 25

O>N>C~H | -

Question 26

Ions

Answer 26

Two oppositely charged atoms (or molecules) ``` Positive = Cation Negative = Anion ```

Question 27

Ionic Bond

Answer 27

Unpaired valence electrons are transferred from one atom to another

Question 28

Hydrogen Bond

Answer 28

Hydrogen bound to an atom that strongly attracts the shared electrons (that is more electronegative)

Question 29

Van Der Waals Interactions

Answer 29

Because they move around the nuclei, electrons are not distributed evenly in atoms or molecules

Question 30

Functional Groups

Answer 30

See textbook!

Question 31

Hydroxyl Group

Answer 31

Is polar due to electronegative oxygen. Forms hydrogen bonds with water, helping dissolve compounds such as sugars Compound name: Alcohol

Question 32

Carbonyl Group

Answer 32

Sugars with ketone groups are called ketoses; those with aldehydes are called aldoses. Compound name: ketone or aldehyde

Question 33

Carboxyl Group

Answer 33

Acts as an acid (can donate H+) because the covalent bond between oxygen and hydrogen is so polar Compound Name: carboxylic acid or organic acid

Question 34

Amino Group

Answer 34

Acts as a base; can pick up an H+ from the surrounding solution (water, in living organisms) Compound name: Amine

Question 35

Phosphate Group

Answer 35

Contributes negative charge (1- when positioned inside a chain of phosphates; 2- when at the end). When attached, confers on a molecule the ability to react with with water, releasing energy Compound Group: organic phosphate

Question 36

Methyl Group

Answer 36

Affects the expression of genes when on DNA or on proteins bound to DNA. Affects the shape and function of male and female sex hormones. Compound name: methylated compound

Question 37

Carbon Bonds

Answer 37

Carbon can complete valence shells by sharing electrons with 4 other atoms

Question 38

Organic Chemistry

Answer 38

The study of compounds containing carbon

Question 39

Hydrocarbons

Answer 39

Organic molecules consisting of only carbon and hydrogen

Question 40

Isomers

Answer 40

Compounds that have the same number of atoms of the same elements but different structures hence different properties

Question 41

Cis-Trans Isomers

Answer 41

(Formerly called geometric isomers) when carbons have covalent Bonds to the same atoms, but these atoms differ in their spatial arrangements due to the inflexibility of double Bonds.

Question 42

Enantiomers

Answer 42

Isomers that are mirror images of each other and that differ in the shape due to the presence of an asymmetrical carbon, one that is attached to four different atoms or groups of atoms

Question 43

Adenosine Triphosphate (ATP)

Answer 43

Consists of an organic molecule called adenosine attached to a sting of 3 phosphate groups