Posted by amy on Tuesday, October 14, 2008 at 9:37pm.
Please repost it . Jan 20 is beyond my recall ability.
I reposted it. but I made it a new string on accident. I am new at this and apparently not very savvy....all apologies. It is still under the same heading of Chemistry and amy is the poster.
Thanks for helping me out on this.
Did you post the problem or the answer?
I posted the question again. a few moments ago. I am new at this site and obviously not very savvy.....sorry. It is the same heading and name. (Chemistry; amy)
thanks for any help you can give.
use the following information to identify element A and compound B and answer the questions. An empty glass container has a mass of 658.572g. It has a mass after it has been filled with nitrogen gas at a pressure of 790 torr and a temp of 15 degrees celcius. When the container is evacuated and refilled with a certain element A at a pressure of 745 torr and a temp of 26 celcius, it has a mass of 669.59g. what is the volume of the container. THe volume is .715 and the element is Cl2.
Compound B a gaseous organis compund that consists of 85.6% carbon and 14.4 % hydrogen by mass, is placed in a stainless steel vessel (10.68L) with excess oxygen gas. The vessel is placed in a constant temp bath at 22. Celcius. The pressure in the vessel is 11.98 atm. in the bottom of the vessel is a container that is packed with Ascarite and a Desiccant. Ascarite is asbestos impregnated iwth sodium hydroxide; it quantitatively absorbs carbon dioxidee. The desiccant is anhydrous magnesium perchlorate, which absorbs the water prduced by the combustion rxn. Neither
the Ascarite nor the desiccant reacts with compound B or oxygen. The total mass of the container with the Ascarite and desiccant is 765.3g
The combustion rxn of compund b is initiated with a spark. The combustion
rxn is B + xO2 --> yCO2 + zH2O (x, y, z, are unkown sotichiometric coefficients. The pressure immediately rises then begins to decrease and finally reaches a steady state value of 6.02atm. The stainless steel vessel is carefully opened, and the mass of the container inside the vessel is found to be 846.7g.
Substances A and B react quantitatively in a 1:1 mole ration to form one mole of the single product, gas C
What is the identity of compound B?
what is the identity of compound C
how many grams of C will be produced if 10.0L of B (each at STP) are reacted by opening a stopcock connecting the two samples?
What will be the total pressure of the system? This is Pt=P1+P2...right?
ok so now I know that the compound is CH2 which was on the other post, but now I understand how to get that. How do you know if it is C2H4 or something else.
OK, you understand the empirical formula, CH2, which is the lowest whole number ratio. To get the true molecular formula, of the same ratio, you have to know the molecularmass. In this problem, you have to solve for x,y,z to determine that (Knowing y, you know the formula for B). Use the gas laws to get x,y,z from the pressure changes.
could you write a balanced equation since you know products and the reactants?
If not I used 10.68 L, and 11.98 atm and R and 295.15K to get 5 mol. the mols of CH2 would be 5. ?
I don't know how to solve for Y. and I am guessing you are at work now....