Answer : The number of moles of
produced will be, 0.241 moles.
Solution : Given,
Mass of Fe = 27.0 g
Molar mass of
= 56 g/mole
First we have to calculate the moles of
.

Now we have to calculate the moles of 
The balanced chemical reaction is,

From the reaction, we conclude that
As, 4 mole of
react to give 2 mole of 
So, 0.482 moles of
react to give
moles of 
Thus, the number of moles of
produced will be, 0.241 moles.
Answer: (E) 300 bq
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
Radioactive decay process is a type of process in which a less stable nuclei decomposes to a stable nuclei by releasing some radiations or particles like alpha, beta particles or gamma-radiations. The radioactive decay follows first order kinetics.
Half life is represented by 
Half life of Thallium-208 = 3.053 min
Thus after 9 minutes , three half lives will be passed, after ist half life, the activity would be reduced to half of original i.e.
, after second half life, the activity would be reduced to half of 1200 i.e.
, and after third half life, the activity would be reduced to half of 600 i.e.
,
Thus the activity 9 minutes later is 300 bq.
Answer:-
1440 cases
Explanation: -
We are told that 1 pallet = 45 bundles.
We are also told that 1 bundle = 32 cases.
We need to find how many cases are there in 1 pallet.
1 pallet = 45 bundles (First conversion factor)
= 45 x 32 cases (second conversion factor)
=1440 cases
Thus we see that 1 pallet has 1440 cases. We needed to use two conversion factors for this, first to convert pallet to bundle and second to convert bundle to cases.