A 0.03 mol sample of NH4NO3(s) is placed in a 1 L evacuated flask, which is then sealed and heated. The NH4NO3(s) decomposes completely according to the balanced equation above. The total pressure in the flask measured at 400 K is closest to which of the following?
January 8, 2009
12th grade chemistry
A piece of iron wire weighs 2.225g. It is dissolved in acid, which oxidizes the iron to iron(II), and made up to 250 mL. A 25mL sample required 31.0 mL of a 0.0185mol/L solution of potassium dichromate. Calculate the percentage of iron in the wire.
November 10, 2008
A 156.5 g piece of stainless steel was heated to 510 C and quickly added to 25.11 g of ice at -30 C in a well-insulated flask that was immediately sealed. What will be the final temperature of the system if there is no loss of energy to the surroundings? How much liquid will ...
October 26, 2008
A 156.5 g piece of stainless steel was heated to 510 C and quickly added to 25.11 g of ice at -30 C in a well-insulated flask that was immediately sealed. What will be the final temperature of the system if there is no loss of energy to the surroundings? Does anyone know how I...
October 26, 2008
I did a lab in chemistry in which 15-mL jumbo Beral pipets with acetone was heated in boiling water until all of the liquid evaporated. Then the pipets were placed into room temperature water so that the evaporated liquid turns into condensed vapor. The molar mass was later ...
September 24, 2008
Trains A and B are traveling in the same direction on parallel tracks. Train A is traveling 40 miles per hour. Train B is traveling 48 miles an hour. Train A passes a station at 10:25 pm. If train B passes the same station at 10:55 pm, at what time will train B catch up with ...
July 27, 2008
In 1992, the life expectancy of males in a certain country was 69.8 years. In 1999, it was 72.6 years. Let E represent life expectancy in year t, and let t represent the numbers of years since 1992.
July 27, 2008
a metallic object is given a positive charge by induction, does the mass change (increase, decrease, same)? what if given a negative charge instead? I think protons has more mass so mass increases and the opposite is true for electrons. Am I right?
February 3, 2008
a new parking lothas spaces for 450 cars. the ratio of spaces for fullsized cars to compact cars is 11 to 4. how many spaces are for full-sized cars? how many spaces for compact cars?
December 12, 2007
I chose raw carrots as my vegetable. According to the chart, the energy gained compared to the energy lost was 10% gained to 90% lost. I would say this is clear evidence that humans need to consume foods closer to the bottom of the food chain so a higher amount of the original...
November 12, 2007
A current of 2.50 A is passed through a solution containing Cu+2 ions for 4.00 hours. Calculate the mass of Cu atoms that form at the cathode. Charge= current*time Convert the charge in coulombs to number of electrons. Since it takes two electrons per Cu+2 atom, divide the ...
May 17, 2007
How much electric charge is needed to produce 1.000kg of Na metal from the Na+ ions in NaCl? You need one electron per atom. How many atoms are present in 1kg of Na? Use avagradros number. To change to coulombs, remember that 1 electron= 1.6E-19C
May 17, 2007
human reason wedded to truth Is this a question? Are we supposed to somehow metaphysically know the question associated with this? Do you have any thinking on this matter? The "truth" is "human" and "reason" are very seldom associated much less &...
March 22, 2007
Describe the climate and physical characteristics of that biome and the types of organisms that live within it. Give examples of and describe symbiotic relationships between those organisms. Be sure to include at least one example from each of the following: parasitism, ...
February 13, 2007
For a dried flower arrangement, customers can choose from 2 types of containers, 3 sample designs, and 2 sizes. How many different arrangments does the shop offer? please post if possible in the by midnight tonight. Thank you
January 23, 2007
I'm in a Grade 12 Data Management Course. The Current unit is Factorials and Permutations. I'm having a trouble with this question. The answer is suppose to be 120 but I dont know how. How many different ways can 6 people be seated at a round table? Explain your ...
September 10, 2006
I need to know how to calculate what percentage of a number is to another. let me make that clearer, 35 is what percent of 48? how is that calculated? What you are asking is this: 35 is to 45 as x is to 100 or 35/48=x/100 solve for x x=.729 Now to get % you must multiply x by ...
August 21, 2005