2 NABr + Ca(OH)2 = CaBr2 + 2 NaOH How many moles of CaB 2 are produced, if 14.72 moles of NaBr and excess Ca(OH) 2 react?

Question

Grateful for any help given!

Answer 1

Hello, Kitty,

The answer is easier than it first appears.

We are provided with a correct balanced equation (I checked).

2 NABr + Ca(OH)2 = CaBr2 + 2 NaOH

This equation is telling us that we'll get 1 mole of CaBr₂ for every 2 moles of NaBr, a molar ratio of 1/2. We'll only get half the moles that we put in of the NaBr. We have 14.72 moles of NaBr, and excess Ca(OH)₂. So the calcium hydroxide is not a limiting reagent: all of the 14.72 moles of sodium bromide will react. The equation says we'll get 1/2 that number of moles of CaBr₂. Therefore, we would expect 7.36 moles of CaBr₂.

I hope that helps,

Bob

Answer 2

A moles-to-moles problem can be solved in one step.

14.72 moles NaBr X 1 mole CaBr₂ / 2 moles NaBr = ________ moles of CaBr₂ produced

In other words, take the number of moles given in the problem and multiply by the mole ratio found by looking at the coefficients in the balanced equation. The balanced equation shows us that for every 2 moles of NaBr that react, 1 mole of CaBr₂ is produced.

Answer 3

the balanced chemical equation here is

2NaBr + Ca(OH)2​ → CaBr2 ​ + 2NaOH,

meaning that the mole ratio between CaBr2 and NaBr is 1:2

since the starting point is 14.72 moles NaBr, you can just multiply!

14.72 moles x (1 mole CaBr2 / 2 moles NaBr) = 7.36 mol

meaning that 7.36 moles of CaBr2 are produced in this scenario