The question is incomplete, here is the complete question:
A chemist measures the amount of bromine liquid produced during an experiment. She finds that 766.g of bromine liquid is produced. Calculate the number of moles of bromine liquid produced. Round your answer to 3 significant digits.
<u>Answer:</u> The amount of liquid bromine produced is 4.79 moles.
<u>Explanation:</u>
To calculate the number of moles, we use the equation:

We are given:
Given mass of liquid bromine = 766. g
Molar mass of liquid bromine,
= 159.8 g/mol
Putting values in above equation, we get:

Hence, the amount of liquid bromine produced is 4.79 moles.
Explanation :
In thermodynamics, a system is region or part of space which is being studied and observed while the surrounding is the region or space around the system which interacts with the system.
Here in the experiment ,system which is observed is reaction or changes when citric acid and sodium bicarbonate are mixed together. And the mixing is carried out in the calorimeter which serves as a surrounding around the system.
The reason behind the using the calorimeter is measure the energy change occurring during the reaction.
Answer:
H3PO4 is stronger than H2PO4- because
H3PO4 dissociation constant is 6.9×10^-3
H2PO4^- dissociation constant is 6.2×10^-8