CH 2 Flashcards
Acids are:
- Sour
- Bitter
Sour
Bases are:
-Sour
-Bitter
Bitter
Which colour do acids turn the colour of litmus to ?
Acids turn blue litmus to red
What colour do bases turn litmus to?
bases turn red litmus blue
Name all natural indicators
Litmus
Turmeric
Red cabbage leaves
Coloured petals of some flowers such as Hydrangea, Petunia and Geranium
Name all Synthetic indicators
Phenolphthalein
Methyl Orange
Name all Olfactory indicators
Onion
Vanilla Essence
Clove oil
Colour of Hydrangea Plant in Acidic and Basic solutions.
Acidic: Blue
Basic: Pink
Colour of Turmeric in Acidic and Basic solutions.
Acidic: No change
Basic: Red
Colour of Phenolphthalein in Acidic and Basic solution.
Acidic: Colourless
Basic: Pink
Colour of Methyl Orange in Acidic and Basic Solution.
Acidic: Red
Basic: Yellow
Smell of Onion in Acidic and Basic solution.
Acidic: Smell retains
Basic: No smell
Smell of Vanilla Essence in Acidic and Basic solution.
Acidic: Smell retains
Basic: No smell
What are Olfactory indicators?
Substances whose odour changes in acidic or basic media.
What are alkalis?
Bases that are soluble in water
What are salts?
Salts are produced due to a reaction between acids and bases
What are Indicators?
They tell us whether the substance that we’re testing is acidic or basic
Colour of litmus solution
Purple dye
Litmus solution is extracted from which plant? and which division does it belong to?
Litchen and it belongs to Thallophyta divison
Acid + Metal gives?
give example:
Salt + hydrogen
HCL + Na –> NaCL + H2
H2SO4 + Zn –> ZnSO4 + H2
Does every metal react with acid?
Only metals which are above hydrogen in the reactivity series can remove hydrogen from acids.
Base + Metal gives?
Give example
Salt + Hydrogen
NaOH + ZnO –> Na2ZnO2(sodium zincate) + H2
Strong acid + Strong base–>
Strong acid + Weak base–>
Weak acid+ Strong base–>
- Neutral salt
- Acidic salt
- Basic salt
Acid + metal carbonate(Co3)–>
Salt + CO2 + H2O
Acid + Metal hydrogencarbonate–>
Salt + CO2+ H2O
What will this form:
HCL + NaHCO3–>
Nacl + CO2 + H2O
What will this form:
H2SO4 + CaCO3–>
CaSO4 + CO2+ H2O
Do bases react with metal carbonates and metal hydrogencarbonates?
If not then why?
Bases do not react with them. because carbonate and hydrogen carbonate are basic in nature and
Base + Base–> no reaction
CaCO3 + H2O + CO2–>
Ca(HCO3)2 (calcium bicarbonate)
Acid + Base–>
Salt + Water
What is Neutralisation reaction?
Reaction between acid and base to give salt and water
Are Metal oxides acidic or basic in nature?
Basic
Metal oxide + acid–>
give example
salt + water
CuO + HCL –>CuCL2 + H2O
MgO+ H2SO4–> MgSO4+ H2O
What is the nature of non-metallic oxides?
Acidic
Non-metallic oxides+base–>
give example
Salt + Water
- Ca(OH)2 + CO2–>CaCO3+H20
-Mg(OH)2+SO2–>MgSO4+H20
name non-metallic oxides
Co2, So2, ClO2, So3, No2
Acids dissolve to give what?
Acids dissolve in water to give H+ or H3O+ ions.
H3O+ is hydronium ion
Bases dissolve in water to give what?
OH- ions
Will the bulb glow if kept in Glucose solution? and what happens in Alcohol?
In neither of them, does the bulb glow. There is any release of H+ ions so current won’t flow.
Testing HCL gas with a dry litmus paper will change the colour to?
There will be no change because acids need water to show its acidic properties. similarly with bases.
Process of dissolving acid or a base in water is a which type of reaction?
Highly exothermic
Which is correct:
- add water to acid all at once
- add acid to base with constant stirring
Option 2
adding water to acid generates head and this may cause the mixture to splash out and cause burns
What is pH scale?
and what does ‘p’ stand for?
A scale for measuring hydrogen ion concentration in a solution.
‘p’ stands for potenz in German = Power
What does 0 and 14 signify in a pH scale?
0 is very acidic and 14 is very alkaline (Basic)
What is the unit of pH?
no unit. just a number
Is this true?
lower the hydronium ion concentration, higher is the pH value?
No.
Higher the hydronium ion concentration, lower is the pH value.
Increase in H+ ion concentration is:
Decrease in H+ ion concentration is:
- Acidic
- Basic
pH of
-our body?
-acid rain
-tooth decay
7.0 to 7.8
lower than 5.6
less than 5.5
which is the hardest substance in the body?
Tooth enamel
enamel is made of?
Calcium hydroxyapatite (crystalline form of calcium phosphate)
What is the nature of bee sting?
Acid (burning pain)
What do stinging hair of nettle leaves inject? solution to this?
Methanoic acid ( burning pain)
rub with leaf of dock plant(grows beside)
which acids do they contain:
-vinegar
-orange
-tamarind
-tomato
-sour milk
-lemon
-ant sting
acetic acid
citric acid
tartaric acid
oxalic acid
lactic acid
citric acid
methanoic
Chemical name of caustic soda
Sodium hydroxide
What is chlor-alkali process?
give equation
when electricity is passed through aqueous solution of sodium chloride (brine) it decomposes to form sodium hydroxide
NaCL + H2O –> NaOH + CL2+ H2
Chemical formula and name of bleaching powder.
Calcium oxychloride
CaOCL2
Chemical formula and name of baking soda.
Sodium hydrogencarbonate
NaHCo3
What causes bread and cakes to rise making them soft?
Carbon dioxide produced when baking soda is added to food
Chemical formula and name for Washing Soda.
Sodium Carbonate Decahydrate
Na2CO3.10H2O
What is water of crystallization?
Water of crystallization is the fixed number of water molecules present in one formula unit of a salt.
it is not free water. it is molecular moisture
How many water molecules are present in one formula unit of copper sulphate?
5
CuSO4.5H2O (Blue vitriol)
Does Gypsum have water of crystallization?
Yes
CaSO4.2H2O
gypsum is a salt
Chemical name of Plaster of Paris.
Calcium Sulphate hemihydrate
CaSO4.1/2 H2O
Heating Gypsum at what temperate loses water to form Plaster of Paris?
373.15 K
