Molarity is defined as the ratio of number of moles to the volume of solution in litres.
The mathematical expression is given as:

Here, molarity is equal to 1.43 M and volume is equal to 785 mL.
Convert mL into L
As, 1 mL = 0.001 L
Thus, volume =
= 0.785 L
Rearrange the formula of molarity in terms of number of moles:

n = 
= 1.12255 mole
Now, Number of moles = 
Molar mass of potassium hydroxide = 56.10 g/mol
1.12255 mole = 
mass in g =
= 62.97 g
Hence, mass of
= 62.97 g
Answer : The work done by the system is, 2.2722 J
Explanation :
The expression used for work done in reversible isothermal expansion will be,

where,
w = work done = ?
n = number of moles of gas = 0.00100 mole
R = gas constant = 8.314 J/mole K
T = temperature of gas = 
= initial volume of gas = 25 mL
= final volume of gas = 75 mL
Now put all the given values in the above formula, we get:


Therefore, the work done by the system is, 2.2722 J
Answer: A little bit confused can you explain what I have to do
Explanation:
A. p block
from 3a-8a are in the p block including halogen
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