How many moles in 1.5×10^23 molecules of nh3?

Explanation:1 mole of stuff

specifies

6.022

×

10

23

individual items of stuff. So you have approx.

2 moles.

Explanation:

You have

1.51

×

10

24

individual ammonia molecules.

Moles of ammonia

=

1.51

×

10

24

⋅

ammonia molecules

6.022

×

10

23

⋅

ammonia molecles mol

−

1

=

approx. 2 moles of ammonia molecules

, but don't trust my arithmetic!

How many moles of nitrogen, of hydrogen, do you have in the specified quantity?

Answer link

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol