Homework Help

A sample of mercury with a mass of 114.0g was combined with 12.8g of oxygen gas, and...

user profile pic

candy1193 | Student, College Freshman | (Level 1) Honors

Posted May 4, 2012 at 5:30 PM via web

dislike 0 like

A sample of mercury with a mass of 114.0g was combined with 12.8g of oxygen gas, and the resulting reaction gave 123.1g of mercury(II) oxide.

How much oxygen was left over after the reaction was complete?

1 Answer | Add Yours

Top Answer

user profile pic

malagala | College Teacher | (Level 2) Adjunct Educator

Posted May 4, 2012 at 5:46 PM (Answer #1)

dislike 2 like

The reaction can be written as,

                                  2Hg + O2 --> 2HgO

 

For the calculation the following molecular weights are considered.

Hg - 200.6 g/mol, O - 16 g/mol

according to the stoichiometric reaction, 401.2 g of Hg reacts with 32 g of O2 and produces 433.2 g of HgO

Hence the amount of O2 that will react with 114.0 g of Hg can be calculated as,

=> (114/401.2)x32

=> 9.1 g

Therefore the amount of excess O2 is = 12.8 g - 9.1 g

                                                       = 3.7 g

 

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes