How can u solve number 'c'?
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Limiting reactant : HNO₃

Given

150 ml 25 g NaOH

150 ml 25 g HNO₃

Required

the limiting reactant

Solution

Reaction

NaOH+HNO₃⇒NaNO₃ + H₂O

Find mol

mol NaOH (MW=40 g/mol):

mol HNO₃(MW=63 g/mol) :

A method that can be used to find limiting reactants is to divide the number of moles of known substances by their respective coefficients, and small or exhausted reactants become limiting reactants

Because from the equation, mol ratio NaOH : HNO₃, so HNO₃ becomes a limiting reactant

can you attach the

c-14 is carbon-14, or radiocarbon.   it is a radioactive isotope of carbon with an atomic nucleus containing 6 protons and 8 neutrons.