[1] Mass of salt (g) 2.005 1.993 [2] Volume of DI water (mL) 49.8 50.0 Mass of DI water (g) [3] Temperature of DI water (°C) 23.4 23.5 [4] Temperature of mixture after dissolution (°C) 20.4 30.9 Temperature difference (°C) -3 7.4 [5] Total mass in reaction (g) 2.1 2.0 Total moles reacted (mol) .026 Total heat of the reaction (cal) [6] Enthalpy of solution ΔHsolution (cal/mol)

The reaction between hydrogen ion and hydroxide ion will be as follows.

so, ratio between hydrogen and hydroxide ions is 1 : 1.

Therefore, moles of  = volume × concentration of

                            =

                             = 0.06 mol

Similarly, moles of  = volume × concentration of

                              =

                             = 0.1 mol

Therefore, ratio of moles of hydrogen and hydroxide ions is as follows.

                                    0.06 : 0.1

                                 = 0.6 : 1

As, hydroxide ions are present in excess so, hydrogen ions are the limiting reagent.

Hence, moles of water formed = moles of  ions = 0.06 mol.

So,    heat released = moles of

                               = 0.062 × 62.0 kJ/mol

                               = 3.72 kJ

                               = 3.72 × 1000 J

                               = 3720 J

Let T is the initial temperature. So,

             Heat released = Heat absorbed by the solution

                                      =

           3720 J =

                         T =

Thus, we can conclude that initial temperature is .                          

passing a magnet thought the

mixture , because iron gets attracted to magnet .

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.