How many liters of fluorine gas are needed to form 879 l of sulfur hexafluoride gas if the following reaction takes place at 2.00 atm and 273.15 k

2637.3 litters of fluorine gas are needed to produce 879 litters of sulfur hexafluoride.

Explanation:

Given data:

Volume of SF₆ = 879 L

Pressure = 2 atm

Temperature = 273.15 k

Volume of fluorine required = ?

Solution:

Balance chemical equation:

    S (s) + F₂(g)    →  SF₆(g)

First of all we will calculate the moles of SF₆.

  PV = nRT

  n = PV/RT

  n = 2. atm× 879L / 0.0821 L. atm. mol⁻¹. K⁻¹  × 273.15 K

  n = 1758 atm. L/ 22.43 L. atm. mol⁻¹

  n = 78.4 mol

78.4 moles of SF₆ will produce.

Now we will compare the moles of SF₆ and fluorine from balance chemical equation.

      SF₆   :   F

        1     :    3

      78.4  :   3/1 × 78.4 = 235.2 moles

Now we will calculate the volume of fluorine.

   PV = nRT

  V  = nRT / P

  V= 235.2 mol. 0.0821 L. atm. mol⁻¹. K⁻¹  × 273.15 K / 2 atm

  V = 5274. 5 / 2

  V = 2637.3 L

2637.3 litters of fluorine gas are needed to produce 879 litters of sulfur hexafluoride.

r just means there's a number of carbon in teh chain. for example rcooh means that after x number of carbon, the chain ends with cooh.

explanation:

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.