Chemistry

Question 1

What is energy and what are the different types?

Answer 1

Energy is the capacity to do work and includes:
1. Kinetic energy
2. Potential energy

Question 2

Kinetic energy

Answer 2

Energy in action

Question 3

Potential energy

Answer 3

Stored (inactive) energy.

Question 4

What are the different forms of energy?

Answer 4

• Chemical energy
• Electrical energy
• Mechanical energy
• Radiant/Electromagnetic energy

Question 5

What is chemical energy?

Answer 5

Stored in the bonds of chemical substances

Question 6

What is electrical energy?

Answer 6

Results from the movement of charged particles

Question 7

What is mechanical energy?

Answer 7

Directly involved in moving matter

Question 8

What is radiant/electromagnetic energy?

Answer 8

Exhibits wavelike properties

Question 9

What is the atomic number of an atom?

Answer 9

The number of protons in an atom

Question 10

What is the mass number of an atom?

Answer 10

The total number of protons and neutrons

Question 11

What is an element?

Answer 11

A pure substance containing only atoms of the same atomic number

Question 12

What is an isotope?

Answer 12

Atoms of the same element containing different numbers of neutrons

Question 13

What are the major elements of the human body?

Answer 13

• Oxygen
• Carbon
• Hydrogen
• Nitrogen

Question 14

What are the lesser elements of the human body?

Answer 14

• Calcium
• Phosphorus
• Potassium
• Sulfer
• Sodium
• Chlorine
• Magnesium
• Iron
• Iodine

Question 15

Is CO2 a molecule, compound, or both?

Answer 15

Both!
Molecule: Composed of two or more atoms
Compound: Composed of two or more elements

Question 16

Is O2 a molecule, compound or both?

Answer 16

Molecule

Question 17

What types of chemical bonds are of the greatest physiological interest?

Answer 17

• Ionic
• Covalent
• Hydrogen

Question 18

Ionic bonds

Answer 18

The attraction of a cation to an anion resulting in the transfer of electrons from one atom to another
(Not a strong bond)

Question 19

Covalent bonds

Answer 19

Sharing of electrons

Question 20

Hydrogen bonds

Answer 20

Weak attraction between slightly positive hydrogen atom and a slightly negative F,O,N atoms

Question 21

Mixtures of other substances in water can be classified as…

Answer 21

• Solutions
• Colloids
• Suspensions

Question 22

What is a solution?

Answer 22

• Homogenous mixture
• Comprised of a solute and solvent that cannot be visually distinguished from each other
• Typically transparent
• Ex: mineral water

Question 23

What is a colloid?

Answer 23

• Heterogenous mixture
• Large solute particles that are too big to pass through a selectively permeable membrane but are small enough to remain permanently mixed with the solvent
• Typically cloudy
• Ex: jello

Question 24

What is a suspension?

Answer 24

• Heterogenous mixture
• Typically cloudy or opaque
• Too heavy to remain permanently mixed with solvent (will separate (“settle out”) on standing)
• Ex: blood

Question 25

What is the difference between mixtures and compounds?

Answer 25

- Mixtures: can be separated physically, not chemically bound - Compounds: can be separated only by breaking bonds

Question 26

Synthesis reactions

Answer 26

- Two or more smaller molecules combine to form a larger one - Bonds are formed (anabolism)

Question 27

Decomposition reactions

Answer 27

- Larger molecules break into two or more smaller ones - Bonds are broken (catabolism)

Question 28

Exchange reactions

Answer 28

- Two molecules exchange toms or groups of atoms - Bonds are both made and broken

Question 29

What is the difference between organic and inorganic compounds?

Answer 29

Organic compounds contain carbon while inorganic carbons do not

Question 30

What are some examples of inorganic compounds within the body?

Answer 30

- Salts: ionic compounds that dissociate in water - Acids and Bases: acids (H+) = proton donors, bases (alkaline, OH-) = proton acceptors

Question 31

What are some examples of organic compounds in the body?

Answer 31

- Carbohydrates - Lipids - Proteins - Nucleic acids

Question 32

What are the properties of water?

Answer 32

- High specific capacity: prevents sudden temperature change - High heat of vaporization: evaporation requires large amounts of heats - Polar solvent properties: dissolves and dissociates ionic substances - Reactivity: necessary for hydrolysis - Cushioning: protects organs from trauma

Question 33

What are some ways that reaction rates can increase?

Answer 33

- Concentration: reaction rates increase when reactants are more concentrated - Temperature: increased temperatures will increase reaction rates - Catalysts: substances that temporarily bind to reactants and hold them in a favorable position to react with each other

Question 34

What is dehydration synthesis?

Answer 34

The joining of monomers to form a polymer (hydroxyl group is removed)

Question 35

What is hydrolysis?

Answer 35

The opposite of dehydration synthesis, polymers are broken into monomers (water ionizes into OH- and H+)

Question 36

What are some of the functions of carbohydrates?

Answer 36

- Cellular fuel - Structural molecules - Storage (glycogen)

Question 37

Lipids

Answer 37

- Insoluble n water (hydrophobic) - Saturated (single bond) unsaturated (double bond)

Question 38

Proteins

Answer 38

- Perform almost all cell functions - Most abundant organic compounds in the body - Polymers of amino acids - Fibrous (structural) and globular (functional)

Question 39

Nucleic acids

Answer 39

-DNA and RNA - Largest molecules in the body Building block = the nucleotide

Question 40

DNA

Answer 40

- GCAT - Double-stranded helical molecule - Provides instructions for protein synthesis

Question 41

RNA

Answer 41

- GCAU - Single-stranded mostly active outside of the nucleus - Three varieties of RNA carry out DNA orders for protein synthesis