Chapter 2 Flashcards
Write down uses of ‘pH’.
Uses of pH
is used to determine acidic or basic nature of a solution It is used to produce medicines, culture at a microbiological particular concentrations of H+ ions.
It is used to prepare solutions of required concentrations necessary for certain biological reactions.
Define conjugate acid and conjugate base.
Conjugate Acid
A conjugate acid is a specle formed by accepting a proton by a base Conjugate Base
A conjugate base is a specie formed by donating a proton by an acid Thus conjugate acid-base pair differs from one another only by a single proton.
Write down characteristic properties of Bases:
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Characteristics Properties of Bases
Taste
Fours hove bitter taste and feel slippery, for example, soop is stopery to touch Effect on Litmus Paper
They turn red tus blu Nature
They are non-corrosive necept concentrated forms of NaOH and KOH
Conductivity
Their aqueous solutions conduct electric current
Give the limitations of Arrhenius concept.
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Limitations of Arrhenius Concept This concept is applicable only in aqueous medium and does not explains nature of ande
and bases in non-aqueous medium
According to this concept, acids and boses are only those compounds which contain hydrogen (H) and hydroxide (OH) lors, respectively
It can’t explain the nature of compounds like CO, NH, etc which are acid and book respectively
What is amphoteric substance? Give an example.
Amphoteric Substances The substance that can behave as an acid; as well as, a base is called amphoteric.
What is the importance of NaC??
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Importance of Sodium Chloride (NaCl)
It is commonly used as a table stand for cooking purpos
it is used for de icing moods in winter
It is used for the manufacture of sodium metal, equitic soda, washing soda.
Write down uses of sodium hydroxide and
magnesium hydroxide.
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Uses of Sodium Hydroxide
Sodium hydroxide is used for manufacturing of soon Uses of Magnesium Hydroxide
Magnesium hydroxide is used as a base to neutralize acidity in the stomach
It is also used for the treatment of bee’s stings
Give a few characteristic properties of salts.
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CHARACTERISTIC PROPERTIES OF SALTS
Chemical Nature
Saita ore ionic compounds found in crystalline form Melting and Boiling Point
They have high melting and boiling points
Water of Crystallization
Most of the salts contain water of crystalization which is responsible for the shape of the
crystal Number of molecules of water are specific for each salt and they are written with the
chemical formula of a sot
Copper sulphate CuSO, SHO
Neutral Compounds
Salts are neutral compounds. Although they do not have equal number of positive and
negative ions, but have equal number of positive and negative charges
Define Arrhenius base. Give an example.
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Arrhenius Base According to Arrheniu
“A base is a substance which dissociates in aqueous solution to give hydroxide ion.
What are indicators? Write names of any two indicators.
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Indicators
Indicators are the organic compounds. They have different colours in acidic and alkaline
solutions. Each indicator has a specific colour in acidic medium which changes at a specific
pH another colour in basic medium
Examples
*Litmus
* Methyl orange
Name the types of salts.
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Following are the names of types of salts
*Normal Salt
*Acidic salt
*Basic Salt
*Double Salt
*Mixed Salt
*Complex Salt
Find out the pH and pOH of 0.001M solution of KOH?
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Problem 10.3
Pg 37 of text book
What are universal indicators?
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Universal Indicator
Some indicators are used as matures. The mixture indicator gives different colours at different
volum Hence, it is used to measure the all of a solution Such a mixed indicator is called Universal indicator or simply pH indicator
Process The pH of schution can be measured by dipping a piece of Universal Indicator paper in the solution. The is then found by comparing the colour obtained with a colour chart.
