The reaction is
CaC₂(s) + 2H₂O (l) -----> Ca(OH)₂ (s) + C₂H₂ (g)
As we have data of gas ethyne (or acetylene), C₂H₂
We can calculate the moles of acetylene and from this we can estimate the mass of calcium carbide taken
the moles of acetylene will be calculated using ideal gas equation
PV =nRT
R = gas constant = 0.0821 Latm/molK
T = 385 K
V = volume = 550 L
P = Pressure = 1.25 atm
n = moles = ?
n = PV /RT = 1.25 X 550 / 0.0821 X 385 = 21.75 mol
As per balanced equation these moles of acetylene will be obtained from same moles of calcium carbide
moles of calcium carbide = 21.75mol
molar mass of CaC₂ = 40 + 24 = 64
mass of CaC₂ = moles X molar mass = 21.75 X 64 = 1392g
Answer:
The element will be 
Explanation:
Given that,
Number of proton = 80
Number of neutron = 81
Number of electron = 79
We know that,
The atomic number is equal to the number of proton.
So, the atomic number is 80.
According to atomic number,
The element will be mercury.
We need to calculate the atomic mass
Using formula of atomic mass

Put the value into the formula


We need to find the element
Using atomic mass and atomic number


So, the element will be

Put the value of A and Z
Hence, The element will be 
Molecules with a plane of symmetry between the chiral centers are achiral and meso. From the given molecules (Picture attached) only (A) compound 1 is meso.
When compounds possess a plane of symmetry between the chiral centers they are called achiral or meso compounds. Among the given compounds (A) compound 1 have a plane of symmetry. So we can say compound one is a meso or achiral compound. Compounds two, three, and four have no plane of symmetry, as you can see in the structures attached. So all other compounds (compound 2, compound 3, and compound 4) except compound one are not meso or achiral.
You can also learn about meso compounds from the following question:
brainly.com/question/29022658
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