What are the types of hardness present in water

☆  Types of hardness

 

Hardness of water is of two types temporary hardness or parmanent hardness not  a days these hardness is determined by the term alkaline and non-alkaline hardness so that these term is used at the place of temporary or parmanent hardness 

It is also expressed as carbonate or non- carbonate hardness 

1. Temporary hardness or carbonate or alkaline hardness :- 

The temporary hardness in water mainly cause by the presence of soluble bicarbonates of calcium and magnessium in water 

By the boilling of this water the temporary hardness of the water could be removed easily 

When dissolved bicarbonates are dicomposed yielding insoluble carbonates and hydroxide which are deposited as a crust at the bottom of the vessel 

*  Calcium bicarbonate -- (heat)---------->      calcium carbonate + water + carbon        dioxide 

*  magnessium bicarbonates ---(heat)-->

    magnessium hydroxide  (insoluble )        +  carbon dioxide 

These insoluble carbonates and hydroxides are further removed by filteration

And the salts of bicarbonates , carbonates etc. are responsible for temporary hardness 

Due to presence of bicarbonates and hydroxides of the hardness causing metal ions it is termed as alkaline hardness and which can be determined by titeration with HCl using methyl orange 

2. Permanent hardness :- 

It is caused due to the presence of sulphates ,chlorides and nitrates of calcium ,magnessium, iron and other heavy metals 

It can't be removed by simple boilling but it can be removed by using some chemical method 

And this kind of hardness is also known as non-alkali hardness

The causing salts are chlorides of calcium and magnessium, simulates of calcium and magnessium, nitrates of calcium and magnessium,  etc. These salts are responsible for permanent hardness in water 

BY :- ADARSH GUPTA 

Hardness of water

HARDNESS OF WATER 

The property of water which prevents the leathering of soap it means it is the soap consuming capacity of water

This property is gained by water due to presence of certain salts in water such as salts of calcium, magnessium and other heavt metals like Al,Fe,and Mn dissolved in water 

Hard Water

Water is classified into two main categories on the basis of its behaviour 

And the classification of water which comes from a natural source are as follows 

1. Hard water
2. Soft water

1.  Hard water :-                                   water which contain the impurities of calcium and magnessium in it and also doesn't produces lather when treated with soap solution this kind of water is known as hard water 

e.g. :- sea water , river water 

2. Soft water :- 

The water which is free from the impurities of calcium and magnessium and it radily produces leather when treated with soap solution it is known as soft water 

e.g. :- rain water 

Rain water 

Thankyou 

By :- ADARSH GUPTA 

Causes of hardness

Causes of hardness of water 

Various salts get dissolved in natural water when it passes over rocks or through the several underlying layers of earth 

The bicarbonates ,chlorides and sulphates of calcium and magnessium are most common salts dissolved in water which makes it hard thus hard water is defined that the water which contain the impurities of bicarbonates, chlorides and sulphates of calcium and magnessium which prevents water from leathering and thats why the hard water never produces leather with the soap solution 

When the water containing calcium and magnessium ion treated with soap (sodium and potassium salts of higher fatty acids like oleic ,palmatic, steric)

So that it does not produces lathe with the soap solution but it produces a white precipitates of the Ca+2 or Mg+2 salts of the corresponding fatty acid 

☆      2C 15 H 31 COONa (sodium                         palmitate) + CaCl2 ---------> (C 15 H             31 COO)2 Ca (calcium palmitate as           a ppt.) + 2NaCl 

☆     sodium palmitate + magnessium                chloride ---------> magnesium                        palmitate (ppt.) + sodium chloride 

☆    sodium stearate (soluble in water )            + calcium chloride ----------> calcium          stearate (ppt.) + sodium chloride 

☆    sodium stearate (soluble in water) +          magnessium chloride ------->                        magnesium stearate (ppt.) + sodium         chloride 

Thats why the leather is formed until all the Ca+2 or Mg+2 ions get precipitated completely 

So that now we can say that the hardness of water can be understan as the soap consuming capacity of the water sample hence, the hard water is not suitable for washing purposes because too much salt get west 

Hard water 

Thankyou
 By :- ADARSH GUPTA 

Terms related to water (part -2)

Some interesting term related to water

Pilling- bedworth rule :- Protective and non- Protective nature of oxide layer mainly depends on pilling-bedworth rule 

According to this rule an oxide is protective or non- porous if the volume of metal oxide is greater then the volume of metal from which it is formed on the other hand oxide layer is non- protective or porous if the volume of metal oxide is less than the volume of the metal from which it is formed because it cannot prevent the diffusion or access of oxygen to the fresh metal surface below 

Pilling-bedworth ratio
                      = voume of the                                                 metal oxide formed                                     /volume of the metal                                   consumed   
      Thus Li, Na, k, etc. And Mg, Ca, Sr,  etc. form porous oxides of volume less than the volume of metals and promotes corrosion continuously non-stop. 
On the other hand metal like Al forms oxides of volume higher than the volume of metal due to the absence of any pores in the oxide film the rate of corrosion rapidly decreases to zero 

                                       

Terms related to water (part -1)

Some interesting terms of water

1. Degree of hardness :- The degree of hardness of water states that the presence of equivalent amount of Caco3
Besides this hardness of water is never present in the form of calcium carbonates because it is insoluble in water and also hardness is actually caused by bicarbonates,  chlorides ,and sulphates of calcium and magnessium 
Calcium carbonate is used as the standard reporting of hardness of water is due to following reasons 

1. The very first reason is that its molecular weight is exactly 100 and its equivalent weight is 50 so ,it makes calculation easy.

2. An another reason for using calcium carbonates is that it is most insoluble salt ,that it can be pricipitated in water treatment process

Formula used for the calculation is 
   
=[weight of hardness producing substances in mg/L]*[100]÷[chemical equivalent of hardness causing substances]*2


MF (multiplication factor) = molar weight of CaCO3/2*chemical equivalent of hardness causing substances 

2. Breake point chlorination or free residual chlorination :- chlorination is done for the the treatment of water for not only to treat the living organisms of water but also to destroy the organic inpurities this process is known as break point chlorination 
While chlorine is added into water it is used for different reaction such as oxidation of reducing substances present ,chlorination of any organic substance and also free ammonia living behind mainly free chlorine which possess disinfection action against paythogenic bacteria it is also known as free residual chlorination 
A typical relationship between the amount of chlorine added to water and the free residual chlorine (experimently determined).
The addition of chlorine at break point is known as break point at which free residual chlorine begins to appear normally all tastes odors disappears at break point.

Caustic embrittlement :- During this phinomina the boiller material becomes brittle due to the accumulation of caustic substance 
It is a form of corrosion caused by high concentration of sodium hydroxide in boiler water 
It is most likely to occur in boillers operating at high pressure where NaOH is produced in the boiler by hydrolysis of some residual Na2CO3o obtained from water softening process like lime soda 

Na2CO3 + H2O -----------> 2NaOH + CO2

The formation of NaOH makes the boiler water caustic this caustic water penitrates into the minute hair cracks present in the inner side of boiller by capillary action 
When the water evaporates and the concentration of dissolve NaOH increases progressively which attacks the surrounding area thereby dissolving the iron of boiler as sodium ferrate.
This causes the formation of irregular inter-angular cracks on the boiller metal particularly at place of high local stress like bends, joints , rivets etc. Caustic embrittlement is a case of stress corrosion and is a localized electrochemical phenomenon. 

Rest of the terms we'll discuss in the 2nd part
By :- ADARSH GUPTA 

IMPURITIES OF WATER

IMPURITIES OF WATER 

1. Water becomes impure when comes in contact with industrial waste
2.  While passing through rocks or through mountains water is contiminated with some fine particles of sand and several soluble minerals
3. It is also contaminated by the organic decomposition of plants and animals 

And rain water is contiminated with the harmfull gasses present in the environment 

So these are some ways through which the source of water gets impurities 

Types of impurities in waters

 

1. Suspended impurities :- water contains some suspended particles wether it is organic or inorganic such as dust particles , animal west etc.

These impurities are known as suspended impurities 

2. Collodial impurities :- The larger particles of the impurities settel down on standing but smaller particles remains diappear in collidial form collidial impurities includes finely dissolved silica particles , clay, organic waste, oxides of aluminium or iron , waste products, anino acid coloring materials

3. Dissolved impurities :- Natural water may contaminated by inorganic salts, gasses , and may be dissolved organic matters

a. INORGANIC SALT : 
     
    i. CATIONS : Ca+2 ,Mg+2 ,Na+ ,K+ ,Fe+2 ,Mn+2 ,Al+3 and traces of Zn+2, Cu+2
    ii. ANION : HCO3-, Co_3 2-, So_4 2-,No3-, Cl- and some harmfull gasses like f-

Besides these calcium metal is very essential for the growth of human beings and so also sodium and potassium metal ions depletion of potassium ions in body leads to unbearable fattigue and in some cases also cause serious health injuries 
Also anion are concerned , chloride and small amount of bicarbonates are also required for maintaining the PH of the stomach
However the presence of floride is highly undesirable in high quantities.

b. Dissolved gasses :- 

Co2, O2, So2, H2S, NH3, and oxides of N2 may dissolve in natural water these are the gasses present in the atmosphere with the polluting air and then contiminates the water while water comes in the contact with these gasses in the form of rain drops 

¤Pathogenic micro-organisms :-

Micro-organisms such as bacteria,  virus, fungi, and algae etc. enters into the water bodies and contiminate the water these microbes also comes from sewage and other wastes these microbes are instrumental in causing various diseases and corrosion 

Weatherit can be controlled by chlorination and by adding small amount of copper sulphate , sodium penta chlorophenate

By :- ADARSH GUPTA 

Source of water

SOURCES OF WATER

The water source can be sub devided into four major parts 

1. Surface water :-

As the word surface states that the water which lies over surface of the earth is known as surface water it may be still water or it may be following water like sea and river respectively

IT IS FURTHER SUB GROUPED IN TWO MAIN CATEGORIES 

¤FLOWING WATER :- This source of water consisting the water source which is seems to be following over the earth surface mainly streams and river water falls in this catogeries mainly the source of river water is mealting of snow,springs and rain 

Even we can't be able to use the river water for the domestic purposes as well as industrial purposes because it contains fine particles of sand and several soluble minerals  

It also contains minerals of soil like chloride, sulphate, bicarbonates of sodium, calcium, iron and magnessium

It also contaminated by the organic west like decomposition of plants and animals ,so it is not fit for the domestic purposes 

River water

Still water :- In this catogeries the source which is not following on the earth surface comes the main source comes of still water are lake, ponds and reservoirs lake water is less contiminates then of river water it contains much lesser amount of dissolve minerals but the continuation of organic west in the still water is much greater than the flowing water

• 

Sea water 

2.Underground water :- As the word underground refers that the water source which is found deep inside the ground is known as ground water besides this underground water is free from several organic inpurities and also from several contaminants it is clear in appearance due to the filteration action of the soil ,gravets and other several layers 

Due to presence of dissolve minerals it is hard in nature and due to its taste it can be used for the drinking purpose but also it is not fit for the industrial uses tube wells ,springs, and wells are the some examples of underground water 

Tube wells 

3. Sea water :- As we studied above that the largest area of earth is covered with the oceans and sea this source of water is impure due to the dissolved impurities which includes the release of industrial as well as domestic waste inside the sea an another reason is that the continious evopuration of the sea water increases the dissolved impurities in the water 
Also this water is not suitable for drinking as well as industrial uses
 

Sea water

3. Rain water :- This water source is familiar with everyone this source of water is obtained by the evopuration of the surface water 
It is purest form of natural water but while comming to the earth it is contiminated with the harmfull gasses present in the environment the gasses such as oxides of carbon ,nitrogen ,and sulphur contiminates this water supply 
Besides this dur to its irregular supply it becomes combursome and much expensive to store this water 

BY :- ADARSH GUPTA 

WATER

   INTRODUCTION 

So,today we'll discuss about the most common thing over the earth which is too essential for the existence of living things on the earth 

Water is one of the most wonderful creation of the nature and is required for the survival of human being on the earth 

Besides this water is very abundent on the earth and it covers abourt 75% of the earths total area 

The total supply of fresh water on the earth is only 2.5% of the total amount of water and rest (97.2%) is present in the form of oceans which is salty even we can't drink this water and also it is not fit for the industrial use

so only some limited amount of water is present over the earth for drinking purposes 

                         

By :- ADARSH GUPTA