How many atoms are there in 5.7 mol of li?

5.8

×

N

A

, where  

N

A

=

Avogadro's Number,  

6.022

×

10

23

⋅

m

o

l

−

1

Explanation:

And  

5.8

⋅

m

o

l

×

6.022

×

10

23

⋅

m

o

l

−

1

=

?

?

What is the mass of this quantity of lithium atoms? Hint, 1 mole has a mass of  

6.94

⋅

g

.

Explanation:

i hope this helps

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