1.
Assertion: When combined with soap, hard water forms a thin layer (precipitates of metal ions) known as scum.
Reason: The presence of calcium and magnesium ions (\(Ca^{2+} and Mg^{2+}\)) in hard water limits the cleaning action of soap.
 
2.
Assertion: Non-biodegradable detergents have straight hydrocarbon chains.
Reason: The bacteria's cannot degrade non-biodegradable detergents.