Intro To Chem, Polarity And Water, Acids And Bases

Question 1

Bulk elements

Answer 1

Those required by the body in large amounts (carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus)

Question 2

Trace elements

Answer 2

Those required in small amounts

Question 3

What are the 3 major parts of an atom

Answer 3

Protons, neutrons, and electrons

Question 4

Electrons

Answer 4

Small particle carrying single negative electrical charge

Question 5

Proton

Answer 5

Large particle in nucleus carrying single positive electrical charge

Question 6

Neutron

Answer 6

“Large” particle (same size as proton) in nucleus carrying NO charge, electrically neutral

Question 7

Atomic number

Answer 7

The number of protons in the atoms of a particular element

Question 8

Atomic weight

Answer 8

The number of protons + neutrons in a particular element

Question 9

Describe how electrons are arranged with atoms

Answer 9

Electrons of an atom are found in one or more Electron shells around the nucleus. Each shell can hold a limited number of electrons

Question 10

Octet rule

Answer 10

Atoms react in a away that leaves the outermost Shell completely filled with electrons, thus achieving a more stable structure

Question 11

Why some atoms are chemicals inert

Answer 11

Atoms whose outermost electron shells are filled already have stable structures and are chemically inactive or inert

Question 12

Valence electrons

Answer 12

The number of electrons in the atoms outer sheet determine whether it will react with another atom

Question 13

Ionic bonds

Answer 13

Atoms gain or lose electrons

Question 14

Covalent bonds

Answer 14

Electrons shared equally

Question 15

Atomic energy and an electrons distance from the nucleus

Answer 15

When an electron absorbs energy, it moves to higher energy levels, farther from the nucleus. When an electron releases energy, it falls to lower energy levels, closer to the nucleus

Question 16

Oxidation

Answer 16

The loss of an electron is in a reaction where electrons are transferred from one atom to another

Question 17

Reduction

Answer 17

During the chemical reaction where electrons are being transferred from on atom to another and there is a gain of an electron

Question 18

Isotopes

Answer 18

Atoms that have the same atomic numbers but different atomic weights they may be stable or they may have unstable atomic nuclei that decompose

Question 19

Explain the phenomenon of radioactive decay

Answer 19

Unstable isotopes are called “radioactive” and the energy or atomic fragments they emit are called atomic radiation

Question 20

Examples of isotopes

Answer 20

Carbon

Question 21

Half-life

Answer 21

The time it takes one half of the atoms in sample to decay

Question 22

Half life in context to determining the age of biological samples or rocks

Answer 22

By determining the ratios of different isotopes of C and other elements in biological Samples and in rocks, were able her to accurately determine when these materials were formed

Question 23

Polar molecules

Answer 23

Has an equal number ofprotons and electrons, but one end of the macula has more than its share of elections (becoming slightly negative) while the other end has less than it shares (becoming slightly positive)

Question 24

How polar molecules form hydrogen bonds with other polar molecules

Answer 24

the attraction ofthe positive H end of a polar molecule to the negative o or N end of another polar molecule

Question 25

Polar V. Non polar

Answer 25

Polar compounds, in the shared electrons spend more time near the atom with higher electronegativity while non polar share electrons equally or have have a symmetrical distribution of charge

Question 26

Hydrophilic

Answer 26

Water loving, molecules mix with water because they are ionic or polar

Question 27

Hydrophobic

Answer 27

Water fearing molecules don’t mix with water because they are non polar share

Question 28

Hydrogen bonds

Answer 28

Waters polar nature causes neighboring water molecules to be attracted to one another. This is an important type of attraction that causes water molecules to cling together when in a liquid form

Question 29

Solution

Answer 29

The resulting mixture of water molecules, sodium cations, and chloride anions

Question 30

Solvent and solutes

Answer 30

Water is called the solvent, and the dissolved ions are called the solutes

Question 31

Why doesn’t oil and water mix

Answer 31

Non polar substances like oil have a uniform distribution of charges around all their atoms. Water molecules are more attracted to one another than to the non polar substances. Nonpolar and polar substances won’t mix

Question 32

Adhesion

Answer 32

When water has a tendency to stick to some surfaces, a property called adhesion

Question 33

Cohesion

Answer 33

When water molecules stick to one another

Question 34

How can plants transport water from the roots to the tops?

Answer 34

Capillary action transports water from the roots of plants all the way to the tops of tall trees. The adhesion of water molecules to the vessels inside the plant and the cohesion of water molecules to each other causes them to pull upward

Question 35

Why does ice float and water freeze from the surface down

Answer 35

Ice is less dense than water so it floats! Ice forms on top of ponds and lakes in the winter while the highest density liquid water sinks to the bottom . This allows aquatic animals to survive in the iwinter

Question 36

Electrolytes

Answer 36

Substances that release ions in water

Question 37

Acids

Answer 37

Electrolytes that release H+ ions in water

Question 38

Bases

Answer 38

Substances that combine with H+ ions

Question 39

PH scale

Answer 39

Shorthand system for describing H+ concentration. Each whole number on the ph scale (0-14) represents a 10-fold difference in H+ ion concentration. As the H+ concentration increase the ph scale number gets smaller

Question 40

Buffer

Answer 40

Substances that acts as a reservoir for H ions, donating them to the solution when their concentration fall and taking them from the solution when their concentration rises