Question

Calcium hydroxide reacts with hydrofloric acid according to the following reaction.

Ca(OH)2 + HF ===> CaF2+ HOH
If 0.5 moles of hydrofloric acid are reacted, what mass of calcium fluoride will be produced?

Answer 1

Answer:

19.52 grams of calcium fluoride will be produced.

Step by step Explanation :
The balanced chemical equation for the reaction between calcium hydroxide and hydrofluoric acid is:

Ca(OH)2 + 2HF → CaF2 + 2H2O

According to the equation, 1 mole of calcium hydroxide reacts with 2 moles of hydrofluoric acid to produce 1 mole of calcium fluoride.

So, if 0.5 moles of hydrofluoric acid react, then the moles of calcium fluoride produced will be half of that, which is:

0.5 moles HF x (1 mole CaF2 / 2 moles HF) = 0.25 moles CaF2

To calculate the mass of calcium fluoride produced, we need to use the molar mass of CaF2, which is:

40.08 g/mol (for Ca) + 2(18.99 g/mol) = 78.06 g/mol

So, the mass of calcium fluoride produced will be:

0.25 moles CaF2 x 78.06 g/mol = 19.52 g

Therefore, if 0.5 moles of hydrofluoric acid are reacted, 19.52 grams of calcium fluoride will be produced.

Answer 2

To answer this question, one must first understand the stoichiometric equation for this particular reaction. The equation states that for each one mole of calcium hydroxide (Ca(OH)2) that reacts with one mole of hydrofloric acid (HF), one mole of calcium fluoride (CaF2) and one mole of water (HOH) is produced. Therefore, if 0.5 moles of hydrofloric acid are reacted with the calcium hydroxide, then 0.5 moles of calcium fluoride will be produced.

To calculate the mass of calcium fluoride that will be produced, one must first look up the atomic mass of both calcium and fluorine and multiply them by the number of moles of each that are present in the reaction. In this case, the atomic mass of calcium is 40.08 and the atomic mass of fluorine is 19. Therefore, the mass of calcium fluoride that will be produced is equal to (40.08 x 0.5) + (19 x 0.5) = 29.54 g.

In conclusion, if 0.5 moles of hydrofloric acid are reacted with calcium hydroxide, then a mass of 29.54 g of calcium fluoride will be produced.