Redo the experiment by clicking on Reset Experiment. Add Ca(NO3)2 to 40 g of Na2CO3 and determine at what point the masses of the two reactants react "evenly." That is, how many grams of Ca(NO3)2 must be added to just consume the 40 g Na2CO3 initially available?

Answer : The mass of  added must be, 61.9 grams

Explanation : Given,

Mass of = 40 g

Molar mass of = 105.9 g/mol

First we have to calculate the moles of .

Now we have to calculate the moles of

The balance chemical reaction will be:

From the balanced reaction we conclude that

As, 1 mole of react with 1 mole of

So, 0.378 mole of react with 0.378 mole of

Now we have to calculate the mass of

Molar mass of = 164 g/mol

Thus, the mass of  added must be, 61.9 grams