Question

Which of the following is not a correct chemical equation for a double replacement reaction?

2 HNO3 + Mg(OH)2 yields 2 H2O + Mg(NO3)2
H3PO4 + 3 NaF yields 3 HF + Na3PO4
2 KNO2 + BaSO4 yields K2SO4 + Ba(NO2)2
Ca + 2H2O yields Ca(OH)2 + H2

Answer 1

Ca + 2H2O --> CA(OH)2+H2
it is not a double displacement reaction.
because only Hydrogen is displaced.