The acid anhydride that will produce weak acid in water is
SO3
NO2
SO2
CO2
Correct answer is D
H2CO3 is an example of a weak acid while H2SO4 and HNO3 are examples of a strong acid.
CO2 combines with water to give a weak trioxocarbonate (IV) acid.
CO2 + H2O → H2CO3
CaCO3
Na2CO3
Na2SO4
CaSO4
Correct answer is A
Permanent hardness in water= Mg & Ca Sulphate.
Temporary hardness in water= Mg & Ca Carbonate.
Temporary hardness of water is caused by Magnesium and calcium hydrogencarbonate. It is formed when rainwater containing dissolved CO2 flows over deposit of CaCO3
i.e CaCO3 + CO2 + H2O → Ca(HCO3)2
The constituent common to duralumin and alnico is
Co
Mn
Al
Mg
Correct answer is C
Constituents of duralumin are: Al, Cu, Mg, Mn.
Constituents of Alnico are: Al, Ni and Co
In 1909, the alloy of duralumin was discovered by Alfred Wilon consisting of 94% Al, 4% Cu, 1% Mg and 1% Mn(Manganese)
Alnico is an acronym referring to a family of iron alloys which in addition to iron are composed primarily of Al, Ni and Co.
The general formula of alkanones is
RCHO
RCOR'
RCOOH
RCOOR
Correct answer is B
Alkanones also known as ketones have the general formula RCOR'
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