Module 1

Question 1

Number of recognized elements in nature

Answer 1

92 elements

Question 2

Subatomic particles

Answer 2

Protons, electrons, neutrons

Question 3

Trace elements

Answer 3

are required by organisms in minute quantities

Question 4

96% of living matter is made up by

Answer 4

C H O N

Question 5

Mass number

Answer 5

protons + # neutrons

Question 6

The number protons defines

Answer 6

the element

Question 7

The number of neutrons can vary and result in

Answer 7

atoms with different mass number, ISOTOPES

Question 8

Isotopes

Answer 8

Have the same number of protons, different number of neutrons

Question 9

Compound

Answer 9

Substance consisting of 2 or more different elements

Question 10

Genome

Answer 10

Library of genetic instructions that an organism inherits

Question 11

Element

Answer 11

Substance that cannot be broken down to other chemical reactions

Question 12

Reactivity happens due to

Answer 12

unpaired electrons in an orbital of the valence shell

Question 13

Chemical bond

Answer 13

Attraction between atoms that make them stay together

Question 14

Covalent Bond

Answer 14

2 atoms share 1 or + outer shell electron. Ex. CH4

Question 15

Electronegativity

Answer 15

Tendency of an atom to attract shared electrons. Ex. Non Polar Covalent Bonds

Question 16

Polar covalent bond

Answer 16

Atoms with different electronegativities bond, the electrons spend more time with the most electronegative . Ex. H2O as O is more electronegative than H

Question 17

Ionic bond

Answer 17

Atracttion between opposite charges. One strips an electron away from its partner to complete the shell

Question 18

Ion

Answer 18

An atom/molecule with an electrical charge from gaining or losing electrons

Question 19

Which are the strongest bonds?

Answer 19

Covalent bond and ionic bond

Question 20

Which bond is the weakest?

Answer 20

Hydrogen bond

Question 21

Non polar covalent bond

Answer 21

Atoms have the same electronegativity. H - H or O = O (same element)

Question 22

Hydrogen bond

Answer 22

Attraction between already bonded hydrogen and an electronegative atom, generally oxygen. Molecules of partial opposite charges

Question 23

Water

Answer 23

Solvent of life, facilitates chemical reactions, easy distribution of dissolved molecules.

Question 24

Radioactive isotope

Answer 24

in which the nucleus decays spontaneously, giving of particles of energy and converting into another element.

Question 25

Molecular mimics

Answer 25

A molecule which produces the same effects as the naturally occuring molecules

Question 26

Electron

Answer 26

Negligible mass (small, insignificant)

Question 27

Cation

Answer 27

Positively charged ion

Question 28

Anion

Answer 28

Negatively charged ion

Question 29

Salts

Answer 29

are ionic compounds, formed by ionic bonds

Question 30

Behaviour of an atom is determined by

Answer 30

electron distribution in the outer shell

Question 31

Chemical reactions involve

Answer 31

making and breaking chemical bonds

Question 32

Molecular shape determines

Answer 32

how biological molecules recognize each other and respond

Question 33

Are radioactive isotopes stables?

Answer 33

No, radioactive isotopes are unstables

Question 34

Hydrophilic

Answer 34

Affinity for water, does not necessarily dissolve

Question 35

Hydrophobic

Answer 35

Repel water, non ionin or non polar

Question 36

internal ph of most living cells is

Answer 36

close to 7

Question 37

ph of human blood

Answer 37

7.4

Question 38

Specific heat of water

Answer 38

4.18 J/g • C

Question 39

Decay process

Answer 39

Nuclei have tendency to lose subatomic particles

Question 40

Stable isotopes

Answer 40

don't have tendency of decay process

Question 41

Unstable isotopes

Answer 41

give off particles & energy as radioactivity, it transforms the atom into an atom of different element

Question 42

Orbitals have

Answer 42

a maximum of 2 electrons

Question 43

Neutral atom

Answer 43

Equal # of electrons & protons

Question 44

Major elements of life

Answer 44

C H O N S P

Question 45

Orbitals

Answer 45

Three dimensional space where max 2 electrons are usually located