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:
A1. Sr + 2
A2. P - 3
B1. Sr3P2
Explanation:
A1. Strontium ion | Sr+2
Description: Strontium(2+) is a strontium cation
Molecular Formula: Sr+2
A2. PubChem CID 5182128
Structure Find Similar Structures
Molecular Formula P-3
B. Strontium phosphide
PubChem CID 166710
Structure Find Similar Structures
Molecular Formula Sr3P2 or P2Sr3
Answer: 126.1 grams of are needed to make 5.3 L of 0.25 M solution
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.
To calculate the mass of solute for given molarity, we use the equation:

Thus 126.1 grams of are needed to make 5.3 L of 0.25 M solution