March 24, 2008

General Chemistry (Part 1): Questions of Basic Stoichiometry

The following questions are about the basic stoichiometry. You may think why I wrote chemistry field again? It ain't a fun part of chemistry. Because I know many students get hard with stoichiometry so I put this field once again. But here are questions only. You need to read 'Let's Try to Learn Stoichiometry' at first and continue reading this part then. Here we go....
  1. Calculate the empirical formula for a compound with the following percent composition: 23.29% of Mg, 30.72% of S and 45.99% of O.

  2. A saturated hydrocarbon contains 82.66% of carbon. what is its empirical formula and molecular formula?

  3. Calculate of the mass of chloride ion in 1.00 liter of each of the following solutions: a) 10% of NaCl (1.07 g/ml of density); b) 1.00 M NaCl; c) Calculate the molarity of the first solution.

  4. Express the following gas pressures in atmospheres: a) 300 cmHg; b) 380 torr.

  5. Calculate the molarity of each type of ion remaining in solution after 20.0 ml of 6.00 M hydrochloric acid is mixed with 50.0 ml of 2.00 M barium hydroxide.

  6. How would one prepare exactly 300 ml of 5.00 M HCl solution by diluting sufficient 12.00 M stock solution.

  7. Calculate the mass of CuS produced and the concentration of hydrogen ion produced by bubbling excess sulfuric acid into 1.00 liter of 0.10 M copper (II) chloride solution.

  8. A refrigeration tank is holding 5.00 liters of freon gas (C2Cl2F2) at room temperature and 3.00 atm of pressure develop a leak. When the leak was discovered and repaired, the tank had lost 76.0 grams of the gas. What was the pressure of the gas remaining in the tank at the room temperature above?

  9. In an auto engine with no pollution controls, about 5% of the fuel (assume 100% octane, C8H18) is unburnt. Calculate the relative masses of CO and C8H18 emitted in the exhaust gas. Calculate the relative volumes of these gases.

  10. When 0.75 mole of a solid "C8" and 2 moles of gaseous oxygen are heated in a seated vessel (bomb), completely using up the reactants and producing only one compound, it is found that when the temperature is reduced to the initial temperature, the contents of the vessel exhibit a pressure equal to half the original pressure . What conclusions can be drawn from these data about the product of the reaction?

Labels: ,

8 Comments:

Anonymous Mr.LooG said...

Iyah yah Bu..
Susah banget stoikiometrinya..
Apalagi yang ibu postkan..
Ampun deh..

Gimana cara jawabnya Bu??
Bisa diajar gak??

March 25, 2008  
Blogger wyd said...

see.... that's why i put those questions here to readers think more. if i also put the answers here, it won't make u use your brain but just read n read, rite?

March 25, 2008  
Anonymous Mr.LooG said...

Gimana kalo sebagai langkah pertamanya, Ibu terjemahin dulu soalnya??

terus, setelah saya bertapa 7 hari 7 malam di gunung Kawi, hasilnya:
1.MgSO3
2.C4H10

March 26, 2008  
Blogger wyd said...

come oonn, i know you use english in your college and you do speak english much better than me.
just try it with yourself first, ok?

March 26, 2008  
Anonymous mr.loog said...

Loohh, saya gak college..
Dan saya gak pake english..

Yang no 1-2 nya itu benar kagak??
Hasil mandi bunga di Gunung Kawi loo Ibu Guru..

Please check this one out as well..
http://olimpiade.org/Forum/viewtopic.php?t=5534

and also:
http://olimpiade.org/Forum/viewtopic.php?t=6143

Thanks b4..

March 26, 2008  
Blogger wyd said...

i'd left my comment in your recommended forum. check it out.

btw... how can u study in UK without using english?
i hope im good enough in guessing....

March 27, 2008  
Anonymous mr.loog said...

I've..
But not in the url that i've told you..:twisted:

After muter2 dan kesasar2 lama2..
But thank god I can check out all of your post from moderator control panel..
So i've found your last post..

I've reply it as well..
Really2 do hope that you want to read it again..

And I wanna beg your pardon as well in here, buat kelakuan kasar dan tidak pantas hanya karena anda adalah seorang guru..(buat selengkapnya tolong dibaca di reply saya di forum..)

I really2 getting annoyed because almost all of your colleagues that i've ever met.. And that's why I run away before I kill or be killed by one of your colleagues..

Anyway..
I learnt chemistry in Bahasa,
not in English..
So I don't understand Chemistry-English..
And I've told you before that i'm not a college student..
So my comment above is totally right..Hehe~

And also:
After you check my reply out,
tell me in here..
I still have another thing to tell you..

And Finally:
Si Ino'x dah lama MATI SURI dari forum itu..
Terakhir log in nya sudah lebih dari 1 taun lalu..
Jadi kalo Ibu Guru masih mo ngomong2 di sono, ngomong2 nya ma saya saja..Haha~

March 27, 2008  
Blogger wyd said...

if u thought u'd rather to use indonesian than english... u can visit my indonesian blog.

nice to see u there, young man!

March 27, 2008  

Post a Comment

Subscribe to Post Comments [Atom]

Links to this post:

Create a Link

<< Home