How many moles of nitrogen gas will be produced by the rapid decomposition of 140 g of azide NaN3 in the reaction? 2NaN3 ⟶2Na +3N2

Given: Formula weight for Na= 23 g/mol, Formula weight N=14 g/mol,

Group of answer choices

1.44 mol

2.12 mol

42 mole

3.23 mol

Flag question: Question 2
Question 22.5 pts
What volume of nitrogen gas do you expect to be produced by the azide decomposition? (Hint: 1 mole of ANY gas occupies 22.4 L at STP)

2NaN3 ⟶2Na +3N2

Given: Formula weight for Na= 23 g/mol, Formula weight N=14 g/mol

Group of answer choices

37.1L

48.2 L

72.4 L

32.3 L

Flag question: Question 3
Question 32.5 pts
How many grams of sodium metal will be produced from 140g of NaN3?

2NaN3 ⟶2Na +3N2

Given: Formula weight for Na= 23 g/mol, Formula weight N=14 g/mol

Group of answer choices

42.0 g

49.5 g

99.0 g

2.15 g

Flag question: Question 4
Question 42.5 pts
How many grams of sodium azide are required to produce 275g of N2?

2NaN3 ⟶2Na +3N2

Given: Formula weight for Na= 23 g/mol, Formula weight N=14 g/mol

Group of answer choices

856 g

957 g

426 g

15 g

Answer is in the file below

tinyurl.com/wtjfavyw

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.

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"