Acid Bases and Sal On fhe basis of +6eir

ChemicaB properttes, all +he Compounds Can be classied into three roups

Acds 2. Base3

3. Salts

Tndicatos Ho ndicator s a dye ohieh tells us uwhciher

b the Substance we are testing an acid ov a base. by Changing Colour. The three main ndicators ave tmus Hey_orange anc phene lpthalei

Ltmus is a matoval Fndkator

obtoined-from the plant ihen. Methyl_orange and Phenol - pthalein are Syathetie indicators

*An aud turns eue dmus to Red *Mehyl Orange 9ives ed coloor in qeid

*Phenolpthalin Colouyless i'n aiq Soluion.

* Gase furn Red Lnusto Blue

Methyl oange ges yeltou coloor in Base

Phenolphalin fndicator qives pink in base Solution

gfectory Tncicators Those substantes shose mell ov

odour chanqe in acidic or bosic Souton ove called olfactory indicators. Onion and vonila are olfoctory Tndi cato%.

he Smel of onion Can't be defected when hey are

reated uoith base HoLseverf they are treated wh acid eir Smell Aemains as USual

Acid t u a Substance which shen dissolved n

water produes H aq rons or [Ho*] fons.

For ecample i

HCL in Natey

Hydroclovic acid chloride

In, )H So+

Sulphuric acid

2

Hat Sot Sulphate

IN

ATER HNO H0+ No NiHic NtraTt

27ante acid These are Ahe auds obtained from plonts

and gnimal material and ave usually weak. e CHric

acid, Tartoric acid, lactic auid ete

Mineral aud These are those acids hich ave obtained

from the minerals of the earth and ave Usually Strong Eq HcL, H,So4, HNO3

STrong ad hese ave the auds which completely

diss ouate în water Jo prodvte a larqe mumber of Hfons.

e4 HCL, H,So4,HNos ete. inhe Soluton

Weak aid + These are the acids uohich partiall

is souate n uwafer andhus produed a Small mo of H'a ions in the Soution. e citric aid, latre

ocd etc.

Concentra fee acic+ 3t te acid ushich contains

minimum possí ble amount of water. în t

Dfluted acid Jt u the acid which Coatain much

more water that in Concentrated add

operties of an acid 1) They have Sour taste. 9 They turn blue Hmus to red

Acidic. Soluhon Conduct elechricity. 9Acid have Corrosive mature cas hey produee buns buns

On he skin.

Chemical properbies of Acids ) Reacton_of acid wih METAL

when acid neacet wih metal, salt correspondmg fo metal and H

are produced

Acid+ Metal Salt + Hydrogen

2HCL +t Ca Cs) Cacl(aq) + H9) Hydrochloric

atid (a) Calciom Chloricde

Keachion_ of acids_with BASE LDhen acic teacts wrth

base then Salt and water is formed. This 7eacton K

Called meutilisation eaction.

Acid + Base Sat + nater

HCLa) + NaoH (aq) Nacl Cag)+ Ho( HyDRoCh LoRIe SopioM water Acid HYDRo xig E Sodium chlovi de

3 Reaction of acids wth meta 0xide Thls rca ehion

imilar to Acid and Base reaction hich means that by reatmg acid wh metal oxicde

, salt and wate are formed

e 2HCLt Na,0 2Nacl Caq) +H0

4) Reatoo of Adids rth meta Carbo nate or meta! yarogencarbonale

Vhen Adel reacs srth metas

Carbonats ov meral hydroqen carbo nats , Salt wafer and Car bon diozide are formed

e 2HCL + NazCoy 2NacL+H0 + Co HCL+Na HCo3 Nacl + Ho + Co

Base ihese are the substanes which when cü ssalvec/N

water prood ute (OH) aq ions in+he Solutio

e.qNa0H Na+ OH (a) Sooliom

dro de

2) NH4OH NH +OH Ca) wate Souble base are Known a3 alkalis

Strang Base hese ave Vhe base which Comp letel

dissociata in water and thus prodoced a large mo. of OH a4 tons nhe Solution. .9 Naok, koH er Weak Base

These are he base which ParEiall lissociate

nwate. Ond hus prodoced a Smal9munber af okions inhe Solution e CaH) , goH).NOH) ete.

Preperties of Base ' They aYe biter h taste. (

2) They turn Red GHmus to blue. 3)Basie Solution also conduet electricit 4) They are Soapy to touch

Chemicat_propertres of Ba ses 4) Reaction of Base wrth Some metal

When a base reaut with a metaltRen a meta Salt and hyerogen 2as ae

formed Base + Metal Salt + Hudrozen

2NaOH Zn Na Zn0 + H p Sodi om Soci um

Hydrocde zincate

Note Not all metals Teach wi+% base Jo torm Salts and

2) Bases each wrth aciols When 8ase react< wit acid

water and a sat are fer med

Base + Acid> Salt twater

NaoH a1) + HcL Nacl + H,o (l) e Base Acid Salt atev

3 Reaeion of _base ith mon meta oniele hen a

base react w mon metal oci cde %en Saltand wateer or med

Base + mon- meta Ocide Salt + Nater

2Na0H + Sos NaSo4 + Ho ()

Sodium Sulphate

PH Scale |Pouer of Hydrogen [Patenz de Hydogen

hc P f any Soluton s inverslpropotona thc Contentraton of H(a4) nthat Soution.

Higher the conc: of

LoweY wi Rl be c PH and Jower -he Concentraton H ons of ons hightr i be t pH

TKe Atrength of acid ov

measured by a Scale of mo'strom o-14 Called base

he p Scale pH

Concentration of H 1on inerease Neuhal

H1on Contentrato

deerease

Points to Remember in pUre watev -fRe Concentwafion of

onS are HT fons and 0H eual.Hence puve water meither audic mov basic. t meutral.

Acds have PH less han * ia) Ba Ses have PH more han T

roblemfo Prachice i An aqueous Sol has Ht ions Iox

mol tHer Or 0.0000004 mok/ LiteY Caleulade ts PH.

So Clven [HJ ons = l6 we kno that

p og [H*J -o 157

= - (-1) Jo lo USing Jogm= mlog m

= To lo

Hence he ven soluton is neutral

portance of PHin dailUft ortance of_P" inexistence of Gvingbeings

Our body works withim the P range of To to 78. iving ovgan isms Can SUYvive

only matrou range of pH when PH of rauin wafer Lessthan 56 t s called acid rain. when aid rain ffoNs In to he Soil or rivey Joser the PH and the Survival of planb and quatic ife în +he

Tiver become di ffcult. 2nportance PH n_Soil:

The Soil whase PH u btw 65 t 13 goed for plart ro-h

Sless han 6 5 t audic and morean T3 6becomes alKaine Sotl.

Inpor tanee of PHin Digestion HCL seCTeted in the sto mach

The pH Chanqes between 1 to 3. At this Low value of PH

the atve Sometime due pepsin becomes

to more Secretion of HCL,here i pain or 177itathon in enzymes mamed

he Stomach. ie aidity. Basic Substances ave taken fo7 Temecy ofthe audty Such os Ma CoH) 4 Ne Hcos These Ore Knouwn as antouds.

4PH chanqe as -fhe caUse of +ooth decay

when the PH of +he mouth

made o£

In he bocdy

Tooth decay starts

Lowey han S.5.Tooth qve

Calcium phosphate and t he bardest substonee

Bacterla present in the .'mouth produce acids

yeleqradaton of Sugar and food parieles Temainun

in mouth affer eatng. Toothpastk are b@sic in mature so

meutralise -he excess acid by pre ved toot to6th deca

s)Self dsfenee by gnmalsrguh chemica_wor faxe Many plorh and animale

psotedthemseves trom enemies by tàJrcing painfull tating acid into h enemy body. e.9 Red- ant

bites and we fee! i*ritat'on as fhis he entey affoxmic aid in Ouv body To get e relief from

the efted of bite basic Substanece ke baking Sod app Lied app Lied a1ound the place af bite. t meuteases a cidc pois on and ve Some relie

Saltts t a Compound formed by reat"} a

metal wih an acid. Znt HSo+ ZnSo4 t H

Nacl + Na+ HCL H

Salts are also ormed when acid reacts with base.

e. HCLt Na0H- Nacl+ HO H2So4 + koH 2S 04 + H20

The Salt of HCL are Called c hdorides Sat of H,So4 ar Called sulphades and Salt of mitric acid are calded Nitrates

Family o Sal The Salts having same +ve and meaatve Tons are Said to belong to a family of galts

NaCl, NaSo4 , Na Nos , NaHCos , CH Coo Na are

all called Sodium Salt CNaT on Common)

another_example Nacl, kcl, Mg cl , Cacl are called

Salt_of_ Choridee Ct common) PH o Salt SolutHon

The acddic SolutHon of many Sal ore meutra but some of them prodo ces adoie Soland Ond Some prodoce bosie Solution when dissolved n wder