what mass of water is needed to completely react with 2.35g of Ca

Answer 1

Write the balanced equation.
Convert 2.35 g Ca to moles. moles = grams/molar mass.
Using the coefficients in the balanced equation, convert moles Ca to moles H2O.
Convert moles water to grams water. moles x molar mass = grams.
Post your work if you get stuck.