Calculate how many moles of no2 form when each of the following completely reacts. 2n2o5(g)→4no2(g)+o2(g) part a 1.0 mol n2o5 express your answer using two significant figures. nothing mol m o l request answer part b 5.4 mol n2o5 express your answer using two significant figures.

Part A: 2.0 mol.

Part B: 10.8 mol.

Explanation:

2N₂O₅(g) → 4NO₂(g) + O₂(g),

It is clear that 2 mol of N₂O₅(g) dissociate to 4 mol of NO₂(g) and 1 mol O₂(g).

Part A 1.0 mol N₂O₅:

Using cross multiplication:

2 mol of N₂O₅(g) produces → 4 mol of NO₂(g), from stichiometry.

1 mol of N₂O₅(g) produces → ??? mol of NO₂(g),

∴ The no. of moles of NO₂ produced = (1 mol)(4 mol)/(2 mol) = 2.0 mol.

Part B 5.4 mol N₂O₅:

Using cross multiplication:

2 mol of N₂O₅(g) produces → 4 mol of NO₂(g), from stichiometry.

5.4 mol of N₂O₅(g) produces → ??? mol of NO₂(g),

∴ The no. of moles of NO₂ produced = (5.4 mol)(4 mol)/(2 mol) = 10.8 mol.

kuchisake

kuchisake-onna (口裂け女, "slit mouth woman ") is a malevolent figure appearing in japanese ghost stories, possibly dating back to the edo period. she takes the form of a masked woman who approaches people and asks them if they believe she is pretty.

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.