Answer:
6
Explanation:
the value is 6 because its an even number
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
1.8 moles of oxygen atoms are present in 30.5 grams of hydrogen peroxide.
<u>Explanation:</u>
First we have to convert the given weight of hydrogen peroxide to molar mass of hydrogen peroxide. So for this, we have to divide the given weight with the molecular mass of hydrogen peroxide.

So,

Second step, in this moles, 2 molecules of oxygen are present. Thus 1 mole of Hydrogen peroxide consists of 2 moles of oxygen. Then,

So, 30.5 grams of hydrogen peroxide consists of 1.8 moles of oxygen.