Chapter 2 Chemistry of life

Question 1

Element

Answer 1

substance cannot be broken down to other substances by a chemical reaction. all atoms have same number of protons

Question 2

compound

Answer 2

substance with 2 or more different elements in a fixed ratio

Question 3

Atom

Answer 3

smallest particles that retain chemical elements. cannot be broken down by chemical reactions

Question 4

Anatomy of atom helium

Answer 4

++ proton and neutron in nucleus
- electrons

Question 4

subatomic particles

Answer 4

neutrons, protons, and electrons

Question 5

Atomic number

Answer 5

number of protons

Question 6

how to find atomic mass

Answer 6

protons + neutrons

Question 7

atomic # of Hydrogen

Answer 7

atomic number= 1

Question 8

atomic # of Carbon

Answer 8

atomic number= 6

Question 9

atomic # of nitrogen

Answer 9

atomic number= 7

Question 10

atomic # of Oxygen

Answer 10

atomic number= 8

Question 11

biologically important elements

Answer 11

“CHNOPS”
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfurs

Question 12

trace element: Iodine Deficiency

Answer 12

results in enlarged thyroid gland.

Question 13

trace element; critical for breathing

Answer 13

Iron, attached to hemoglobin to bring in the oxygen

Question 14

Isotopes

Answer 14

elements with the same # protons but different # of neutrons

Question 15

what results from a chemical bond

Answer 15

attraction between atoms

Question 16

incomplete valence shells

Answer 16

can share, trade, or transfer valance electrons

Question 17

covalent chemical bonds

Answer 17

share a pair of valance electrons between 2 atoms

Question 18

what happens to electron in an ionic chemical bond

Answer 18

trade off/ receive

Question 19

hydrogen chemical bond

Answer 19

weak, attracted by partial charges between hydrigen and electronegative atom

Question 20

Electronegetivity

Answer 20

each atom, the density and # of electrons in valance shell determines how strongly the atoms hold on to the electrons

Question 21

higher density and complete valance shell

Answer 21

higher electronegativity

Question 22

electronegativty of oxygen and hydrogen

Answer 22

oxygen- most electronegative
hydrogen- least electronegative

Question 23

polar

Answer 23

partial charge

Question 24

Ionic Bonds

Answer 24

cation and anions attract each other

Question 25

Cation

Answer 25

+ charged after giving away - electron

Question 26

Anion

Answer 26

receive electron - electron

Question 27

Two or more atoms held together by covalent bonds constitute a

Answer 27

molecule