UNIT 4 HIMO CLAY The hydrosphere is the mass of water found on,
under and over the Earth. Approximately three quarters of the Earth
is water. Answer: How much water is there for human consumption on
Earth? Ep!ain" Water is distributed very unevenly on our planet.
Most of it can be found in a liquid state (about !"#,
butwecanalsofinditinasolidstate,thatisinthe form of ice, and in a
smaller quantity as vapour in the atmosphere. H# $: Unit 4
Acti%it&:Inthefo!!owin'photo'raphs&oucanseethe(ifferentwa&s
water is foun( on Earth" I(entif& them an( write (own their
names" 1 234 5876 910 #ater is a mo!ecu!e that is ma(e up of atoms
from two e!ements) h&(ro'en an( o&'en" Each mo!ecu!e is
ma(e up one atom of o&'en an( two atoms of h&(ro'en" The
(efinition of water is as fo!!ows: water is a co!our!ess) o(our!ess
an( taste!ess !i*ui(" $%& #ater is a su+stance with uni*ue
properties that ma,e it essentia! for !i%in' +ein's" -ome of those
properties are the net ones: ' .ro/en water) ha%in' a !ower
(ensit&) f!oats on !i*ui( water" Than(s to this, althou)h the
surface of rivers, la(es and seas can be fro*en durin) winter,
their interior remains liquid and livin) thin)s can survive there.
' #ater is the +est ,nown so!%ent. +t dissolves almost everythin),
except fats. Than(s to this, livin) thin)s can absorb and transport
substances in their bodies. ' #ater re'u!ates the temperature" +t
needs a lot of heat to increase its temperature, but it also loses
heat very slowly. Than(s to that the climate is re)ulated and the
temperature of our bodies is constant. H# 0 UNIT 4: Acti%ities
$)0)1) an( 4 -ea water is sa!t& Each !itre contains a+out 12
'rams of (isso!%e( sa!ts" It contains (isso!%e( 'asesmain!&
nitro'en) o&'en an( car+on (ioi(e" The 'ases are (isso!%e( in
the water +& two processes: ' The mo%ement of the wa%es which
mies water with air ' The acti%it& of a*uatic +ein'sO&'en
is pro(uce( +& photos&nthesis of a*uatic p!ant an( !i%in'
thin's +reathe out car+on (ioi(e The temperature %aries with
(epthAt the sea surface) the temperature is hi'her" In the (eepest
/ones) the temperature of the water is !ower" Ocean waters mo%e in
three wa&s: ' #a%es: Occur on the surface" The& are cause(
+& the win(" #a%es action causes c!iff erosion an( creates
+eaches" #a%es transport san( a!on' the coast an( out to sea '
Ocean currentsare masses of water which mo%e !i,e ri%ers throu'h
the sea" The currents are pro(uce( +& win() (ifferences in
temperature) an( (ifferences in sa!init&" ' Ti(esare the
perio(ic rise an( fa!! of the sea !e%e!" The& are cause( +&
the 'ra%itationa! attraction of the Moon an() to a !esser etent)
the -un" H# 0 UNIT 4: Acti%ities 2)3)4) an( 5 Continenta! water is
fresh waterIt contains much !ess sa!t than sea water" It is foun(
in (ifferent forms: ' -tream or torrents: are water courses fe(
+& rain" The f!ow of water %aries a !ot from season to season"
' #et!an(s: are areas where the 'roun( is inun(ate( a!!
&ear"i"e" marsh!an(s an( swamps ' 6!aciers: are forme( from the
accumu!ation of snow on mountain tops" ' 7i%ers: are permanent
water courses" ' 6roun(water: is water !ocate( +eneath the 'roun(
surface ' La,e: are +o(ies of water of (ifferent si/es containe( on
a +o(& of !an(" H# 0 UNIT 4: Acti%ities 8)$9) an( $$ The water
c&c!e is the mo%ement of water aroun() o%er an( throu'h the
Earth" It consist of the fo!!owin' processes: ' E%aporation: Li*ui(
water chan'es to a 'as :water %apour;" #ater passes from the
h&(rosphere to the atmosphere" ' E%apotranspiration: #ater
e%aporates into the atmosphere from the !ea%es an( stems of p!ant"
' Con(ensation: #ater %apour chan'es to !i*ui() formin' c!ou(s an(
(ew ' T92(?it,E.I The consumption of water has increase(
a!armin'!&" #e use it: 'To satisf& the +asic nee(s:
fee(in') h&'iene) etc" :a+out 2 (ai!& !iters per person;"
'To impro%e our *ua!it& of !ife: to wash) to c!ean) etc" :a+out
59 (ai!& !iters per person;" 'To 'enerate wea!th: a'ricu!ture)
in(ustr&) transport) etc" :a+out 1)099 (ai!& !iters per
person;" '.or recreationa! acti%ities: maintenance of faci!ities)
etc" To o+tain it we nee( reser%oirs) we!!s or (esa!ini/ation
processes" H# 1 UNIT 4: Acti%ities @rin,in' water or pota+!e
wateriswatersafe enou'hto+econsume( +&humansoruse(with
!owris,ofimme(iateor !on' term harm" Toobtaindrin(in)water
weuseaspecialprocess called,drin(in)water treatment-. H# 1 UNIT 4:
Acti%ities #ater po!!ution is an& chan'e to water that has a
harmfu! effect on peop!e or other !i%in' +ein's" -ome po!!utants)
such as iron or copper) ma,e water unp!easant to (rin, or wash in"
Other po!!utants) such as mercur& or +en/ene) can cause
sic,ness or e%en (eath" Man& human acti%ities pro(uce wastes
that can en( up in water" LetAs !oo, at some of them:' -ewa'e water
from towns an( cities" It must un(er'o a sewa'e treatment +efore
returnin' it to the ri%er or +efore usin' it a'ain"'A'ricu!tura!
wastes that are fi!tere( into the soi! an( po!!ute ri%ers an(
'roun(water" .or eamp!e) ferti!i/ers or pestici(es" ' In(ustr&
an( minin' wastes carr& chemica! su+stances such as !ea( or
mercur&" ' Oi! an( petro!) such us oi! s!ic,s or oi! spi!!s" '
Aci( rain) (ue to chemica! reactions +etween rain water an(
atmospheric po!!utants" It harms forests) !a,esB an( a!! their
!i%in' thin's"
http:==www"e(istri+ucion"es=ana&ae(ucacion=5409940=-C$CUNI8=unitC98C%i(eoC90"htm!
H# 1 UNIT 4: Acti%ities SEWAGE WATER TREATMENT
