BIO - CH.2

Question 1

What is a proton, where can it be found, what charge does it carry?

Answer 1

A proton is a subatomic particle found in the nucleus of every atom. It carries a positive charge.

Question 2

What is an electron, where can it be found, what charge does it carry?

Answer 2

• a subatomic particle that can be found orbiting the nucleus and it has a negative charge.
• The reactivity of atoms depends

Question 3

What is a neutron, where can it be found, what charge does it carry?

Answer 3

The neutron is a subatomic particle that can be found in the nucleus and it carries no charge, they are neutral. (They have the same mass as a proton)

Question 4

How Is a covalent bond formed?

Answer 4

chemical bond that involves the sharing of electrons to form electron pairs between atoms.

Question 5

How is an ionic bond formed?

Answer 5

when electrons are completely transferred (moving from one place to another ) from one atom to another. This allow atoms to achieve stability through the transfer of electrons

Question 6

What is an isotope and how does it differ from other atoms of the same element?

Answer 6

• Isotopes have different numbers of neutrons.
• isotopes of elements are named by their mass

Question 7

What are Van der Waal forces?

Answer 7

Van der waals forces are relatively weak electric forces that attract neutral molecules to one another in gasses, in liquefied and solidified gasses, and in almost all organic liquids and solids.

Question 8

Give an example of a Van der Wall force?

Answer 8

hydrogen bonding

Question 9

Why are Van der Waal forces important?

Answer 9

determine how strong dipole moments will be in polar covalent molecules

Question 10

Why does water expand when it freezes?

Answer 10

This expansion occurs because when the water freezes, the water molecules arrange themselves in a six-sided crystalline structure that contains many open spaces.

Question 11

What makes a molecule polar?

Answer 11

A molecule is polar when they have opposite and negative charges that attract each other.

Question 12

Give an example of hydrogen bonding

Answer 12

water molecules

Question 13

Are hydrogen bonds stronger or weaker than ionic or covalent bonds?

Answer 13

Hydrogen bonds are weaker than ionic or covalent bonds but stronger than van der Waals forces.

Question 14

Define cohesion.

Answer 14

attractions between molecules of the same substance

Question 15

Define adhesion.

Answer 15

attraction between molecules of different substances

Question 16

Give an example of cohesion

Answer 16

Water

Question 17

Give an example of adhesion

Answer 17

Water droplets on window

Question 18

What are the two parts of a solution?

Answer 18

Solvent and suspension

Question 19

What is pH a measurement of?

Answer 19

pH is the measure of how basic or acidic a substance is

Question 20

What is the range of the pH scale?

Answer 20

0-14

Question 21

What is the difference between water and an acidic solution?

Answer 21

Water has a pH scale of 7 (making it neutral) while an acidic solution has a pH scale less than 7.

Question 22

What is the difference between water and a basic(alkaline) solution?

Answer 22

Water has a pH scale of 7 (making it neutral) while a basic solution has a pH scale more than 7.

Question 22

What does a buffer do?

Answer 22

• Buffers are a way to help control pH
• Buffers: are weak acids or weak bases that react with strong acids or bases to prevent sudden pH changes

Question 23

Describe the three types of covalent bonds carbon can form, include the number of electrons for each case.

Question 24

What is a polymer?

Answer 24

any of a class of natural or synthetic substances composed of very large molecules, called macromolecules, which are multiples of simpler chemical units called monomers.

Question 25

How are polymers formed?

Answer 25

Monomers join together to make polymer chains by forming covalent bond

Question 26

What is a monomer, and how do they compare to polymers?

Answer 26

A monomer is a single atom, small molecule, or molecular fragment that, when bonded together with identical and similar types of monomers, form a larger, macromolecule known as a polymer.

Question 27

Describe a carbohydrate

Answer 27

• Carbohydrates, or carbs, are sugar molecules. Along with proteins and fats, carbohydrates are one of three main nutrients found in foods and drinks. Your body breaks down carbohydrates into glucose. Glucose, or blood sugar, is the main source of energy for your body’s cells, tissues, and organs. Carbohydrates are compounds made up of Carbon, Hydrogen, and Nitrogen, Usually in a ratio 1:2:1
• Living things use carbohydrates as their main source of energy. Plants and some animals also use Carbohydrates as a structural molecule.

Question 28

Describe lipids

Answer 28

Lipids are fatty, waxy, or oily compounds that are soluble in organic solvents and insoluble in polar solvents such as water. Lipids include: Fats and oils

Question 29

Describe nucleic acids

Answer 29

Nucleic acids are macromolecules containing hydrogen, oxygen, nitrogen, carbon and phosphorous

Question 30

Describe proteins

Answer 30

• Proteins are macromolecules that contain nitrogen, carbon, hydrogen and oxygen
• Proteins are polymers made from amino acids

Question 31

In a chemical equation, on what side of the field’s arrow would you find the reactants?

Answer 31

Chemical equations are written with the reactants on the left side of the equation

Question 32

IN a chemical equation, on what side of the yield arrow would you find the products?

Answer 32

Chemical equations are written with the products on the right side of the equation

Question 33

What is a catalyst?

Answer 33

substance that causes a chemical reaction to take place more quickly by lowering the activation energy required for a reaction to proceed

Question 34

Where would you find the catalyst written in a chemical equation?

Answer 34

It can be included in the reactant side or written above the arrows to indicate its presence

Question 35

State the law of the conservation of mass(matter)

Answer 35

Matter can not be created or destroyed, only transformed.

Question 36

What term is used to describe a reaction that must absorb energy to occur?

Answer 36

Chemical reactions that absorb (or use) energy overall are called endothermic.

Question 37

What term is used to describe a reaction that gives off energy when it occurs?

Chemical reactions that release energy are called exothermic

Answer 37

Chemical reactions that release energy are called exothermic

Question 38

What is activation energy?

Answer 38

The amount of energy required to start a chemical reaction is called activation energy

Question 39

What is an active site on an enzyme?

Answer 39

Enzymes provide a site on themselves that is used to bring reactants close together enough for a reaction to take place

Question 40

What is an enzyme?

Answer 40

Enzymes are proteins that act as biological catalysts

Question 41

Why are enzymes biologically important?

Answer 41

Enzymes help speed up chemical reactions in the human body. They are essential for respiration, digesting food, muscle and nerve function, among thousands of other roles. Each cell in the human body contains thousands of enzymes.

Question 42

What is a substrate?

Answer 42

The molecules that fit into active site

Question 43

Name three variables that can effect the rate of an enzyme catalyzed reaction.

Answer 43

• Temperature
• pH
• Substance concentration