Hydrogen Gas Lab

Purpose The purpose of this lab is to produce hydrogen gas from magnesium and hydrochloric acid and to determine how much hydrogen gas was made. Materials: plastic bin, gas tube, beaker, size 00 two holed stopper, thin copper wire, magnesium, ribbon, thermometer, ringstand, clamp, 10mL 6M HCl. MSDS information Magnesium ribbon- stable, harmful if swallowed/inhaled, wear safety goggles Copper wire- stable, only harmful is dust, precautions needed only if dust Hydrochloric acid- stable, corrosive, poisonous, burns, use suitable ventilation and safety goggles. Hypothesis If we combine known amounts of magnesium and hydrochloric acid then we will produce an amount of hydrogen gas that can be measured with a battery jar and predicted theoretically based on the amount of reactants. Data Run one

Run two

Temperature of air(⁰C)

23.4

23.2

Temperature of water (⁰C)

26.7

24.8

Length of ribbon (cm)

3.52

3.11

Volume of gas (mL)

44.41

39.8

Atmospheric pressure (torr)

79.69

79.69

Description of reaction

Small bubbles at first generated, bubble size increased gradually, reaction suddenly stopped

Small bubbles at first generated with larger bubbles trailing smaller ones, bubble size increased gradually, reaction suddenly stopped

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Results Partial pressure of water vapor= (Partial pressure of water at 24⁰C - Partial pressure of water at 23⁰C)* (temperature of air-23⁰C) + Partial pressure of water at 23⁰C Run one: Pressure of water vapor = (22.4torr-21.1torr)*(23.4⁰C-23⁰C) + 21.1torr= 21.6torr Run two: Pressure of water vapor = (22.4torr-21.1torr)*(23.2⁰C-23⁰C) + 21.1torr= 21.4torr Pressure of hydrogen gas= Pressure of hydrogen gas and water vapor- pressure of water vapor Run one: Pressure of hydrogen gas= 79.69 torr -21.6 torr=53.5torr Run two: Pressure of hydrogen gas= 79.69 torr -21.4 torr=58.3torr Moles of hydrogen gas = Pressure of hydrogen gas* volume of hydrogen gas /(R* temperature of water) Run one: Moles of hydrogen gas = 53.5 torr* .04441 L /(62.37 torr L/moles*⁰C* 26.7⁰C)=.00143 moles hydrogen gas Run two: Moles of hydrogen gas = 58.3 torr* .04441 L /(62.37 torr L/moles*⁰C* 23.2⁰C)=.00179 moles hydrogen gas

Teamwork Skills Peter: I shared the process of recording with John and encouraged him to help make sure water was not leaking from the gas tube while he persuaded me to hold the tube in a different way.

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