A student in Chemistry wanted to determine the value of R and so used the reaction: Mg(s) + 2 HCl(aq) → H2(g) + MgCl2 (aq)  She got a piece of magnesium ribbon and determined its mass as 0

Subject:ChemistryPrice:2.84 Bought7

Share With

 A student in Chemistry wanted to determine the value of R and so used the reaction:

Mg(s) + 2 HCl(aq) → H2(g) + MgCl2 (aq) 

She got a piece of magnesium ribbon and determined its mass as 0.0841 g. She placed the ribbon in a test tube with water and excess HCl and inverted it to allow the H2 gas to bubble to the top of the tube while water was pushed out the bottom. She measured the volume of the gas in the tube as 87.8 mL. She measured the temperature of the water at 20.5?C and the atmospheric pressure in the room was 751 torr.  

 

1- What other piece of information did she have to determine in order to accurately calculate R? 

2- What did she calculate for the value of R? 

3- What was her % error?