Bio 1112009

Dra . María I. Lázaro

Table 2-2 Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.

Figure 2-6b Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.

8p+

8n

(b) Polar covalent bonding

(oxygen: slightly negative)

(–)Water(H2O or H—O—H)

(hydrogens:slightly positive)

(+) (+)

Electrons spendmore time nearlarger nucleus.

smallerpositivecharge

largerpositivecharge

Figure 2-14 Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.

hydrogen ion(H+)

hydroxide ion(OH–)

water(H2O)

(+) (–)

Table 2-2Page 36

Figure 2-15 Biology: Life on Earth 8/e ©2008 Pearson Prentice Hall, Inc.

H+ concentration in moles/liter

increasingly acidic increasingly basic

neutral(H+ = OH–)

(H+ > OH–) (H+ < OH–)

100 10–1 10–2 10–3 10–4 10–5 10–6 10–7 10–8 10–9 10–10 10–11 10–12 10–13 10–14

1mol

ar s

odiu

mhy

drox

ide

(NaO

H)

1mol

ar h

ydro

chlo

ricac

id (

HC

I)

10 2 3 465 7 8 9

stom

ach

acid

(2)

lem

on ju

ice

(2.3

)"a

cid

rain

" (2

.5–5

.5)

tom

atoe

sbe

er (

4.1)

vine

gar,

col

a (3

.0)

oran

ge (

3.5)

blac

k co

ffee

(5.0

)

norm

al r

ain

(5.6

)

wat

er fr

om fa

ucet

urin

e (5

.7)

milk

(6.

4)

pure

wat

er (

7.0)

seaw

ater

(7.

8–8.

3)

saliv

abl

ood,

sw

eat (

7.4)

baki

ng s

oda

(8.4

)

toot

hpas

te (

9.9)

hous

ehol

d am

mon

ia (

11.9

)w

ashi

ng s

oda

(12)

oven

cle

aner

(13

.0)

chlo

rine

blea

ch (

12.6

)ph

osph

ate

dete

rgen

ts

drai

n cl

eane

r (1

4.0)

1110 12 13 14pH

value

Figure 2-17Page 37