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Topic: NEED URGENT HELP  (Read 1496 times)

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Offline 123213

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NEED URGENT HELP
« on: August 27, 2019, 10:20:09 PM »
hey all, recently in class I did an experiment in which hydrogen gas was produced from Mg and HCl. The gas was produced in two different experiments, with one being the gas produced, and the other being the amount of water displaced. With this data i am expected to compare the experiments to both each other and the theoretical value, however i am finding it difficult to calculate both the theoretical volume and a way in which i can compare the experimental to the theoretical. It would be brilliant if someone here could calculate the theoretical and the experimental molar volume and number of moles. Experimental data is listed below

Thankyou in advance


Comparison of the Production of Hydrogen Gas using Different Methods

Method                                           Test 1   Test 2   Test 3   Test 4   Test 5   Average
Water Displacement Method (mL)   73           67            77           94          75         77.2
Gas Production Method (mL)           56           53            57           58           55         55.8

Offline hypervalent_iodine

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Re: NEED URGENT HELP
« Reply #1 on: August 28, 2019, 12:39:50 AM »
hey all, recently in class I did an experiment in which hydrogen gas was produced from Mg and HCl. The gas was produced in two different experiments, with one being the gas produced, and the other being the amount of water displaced. With this data i am expected to compare the experiments to both each other and the theoretical value, however i am finding it difficult to calculate both the theoretical volume and a way in which i can compare the experimental to the theoretical. It would be brilliant if someone here could calculate the theoretical and the experimental molar volume and number of moles. Experimental data is listed below

Thankyou in advance


Comparison of the Production of Hydrogen Gas using Different Methods

Method                                           Test 1   Test 2   Test 3   Test 4   Test 5   Average
Water Displacement Method (mL)   73           67            77           94          75         77.2
Gas Production Method (mL)           56           53            57           58           55         55.8

No one is going to do your work for you, as it is against the forum rules and doesn't really help you in your learning. Could you show your attempts? Where are you getting stuck? You also are missing some information in your post. How much Mg and how much HCl did you use?

Offline Enthalpy

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Re: NEED URGENT HELP
« Reply #2 on: August 28, 2019, 06:30:48 AM »
In addition, I'd find abnormal to seek a third estimate to choose between two incompatible results. Two methods can give the same wrong result and the third be correct. The normal way is to find out what gave different results between gas production and water displacement.

How was the water displacement computed? If water raised somewhere, maybe it dropped elsewhere? What area was taken in the computation?

Offline Vidya

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Re: NEED URGENT HELP
« Reply #3 on: August 29, 2019, 01:09:36 AM »
if someone here could calculate the theoretical and the experimental molar volume and number of moles. Experimental data is listed below

Basically you are asking us to do all calculations related with this experiment.
We can guide you how to do calculations/
First you need to check amount of Mg and HCl you used in experiment and then use  Stoichiometry(calculating the amount of product from limiting reactant).This will give you theoretical yield.
You preformed experiment  by two ways and volume of  gas is more when it is collected by water displacement because it is not pure H2 .It is H2 mixed with water vapors,so use gas equations to get volume of dry H2 and that will be experimental yield.   

Offline Enthalpy

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Re: NEED URGENT HELP
« Reply #4 on: August 29, 2019, 04:39:41 AM »
It is H2 mixed with water vapors,so use gas equations to get volume of dry H2 and that will be experimental yield.

2% correction won't explain the discrepancy.

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