Post Laboratory Questions 1. The reaction of magnesium with hydrochloric acid is
ID: 1026375 • Letter: P
Question
Post Laboratory Questions 1. The reaction of magnesium with hydrochloric acid is a redox reaction. Identify which species is being oxidized and which is being reduced 2. How would each of the following common errors affect the calculated moles of H2 produced? Calculated value would be too high, too low, or no different from true value. Explain each answer. a. Student forgot to subtract the pressure of the water. b. Student forgot to convert temperature to Kelvin A student forgot to fill the tubing with water before the start of the experiment c. d. The student tipped over the Mg vial and started a small amount of reaction before replacing the stopper in the flask e. The student used a beaker that contained several mLs of water from a prior trial to collect the water displaced by the hydrogen. 3. If 0.12 g of Mg reacted with 23.21 mL of 1.00 M HCI. How many moles of HCI would be in excess?Explanation / Answer
The reaction between Magnesium and HCl is given as :
Mg (s) + 2 HCl (aq) -----------------> MgCl2 (aq) + H2 (g)
where
Mg element goes form oxidation state zero (0) to magnesium ion Mg2+ ( Oxidation State = 2+ ) thus magensium is being oxidised.
and
HCl goes from H+ ( Oxidation state. = + 1 ) to hydrogen gas , H2 ( oxidation state = 0) thus HCl is being reduced.