Best answer answer
5m hcl in 50ml reacts with 5g mno₂. calculate the mass of mncl₂ and volume of cl₂.

The answer to your question is:

a) 1.12 l of Cl2

b) 6.3 g of MnCl2

Explanation:

Reaction

                   4HCl + MnO2 ⇒  Cl2 + 2H2O + MnCl2

Data

HCl 5M, 50 ml (0.05 l)

MnO2 = 5 g

MW MnO2 = 87 g

MW MnCl2 = 126 g

Process

For HCl

M = n/V

n = MV

n = 5(0.05) = 0.25 moles     from the reaction 4(0.05) = 1 mol of HCl

For MnO2

                        87 g 1 mol

                           5 g   x

                         x = 5/87 = 0.05 mol of MnO2

The proportion in the reaction HCl to MnO2 is 4:1 but from the operations,  

1: 0.05, the from this we see that MnO2 is the limiting reactant, and we take MnO2 to obtain the values of the questions.

a)  From the reaction        1 mol of MnO2 1 mol of Cl2

                                          0.05 mol               x

                                          x = 0.05 moles of Cl2

                        1 mol of Cl2  22.4 l

                        0.05 moles       x

           x = 0.05 x 22.4/1 = 1.12 l

b) From the reaction        1 mol of MnO2 1 mol of MnCl2

                                        0.05 mol of MnO2   x

                                        x = 0.05 moles of MnCl2

                                        1 mol of MnCl2  126 g of MnCl2

                                       0.05 mol of MnCl2    x

                        x = 0.05 x 126 = 6.3 g

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.