Given the reaction: 2 H2(g) + O2(g) → 2 H2O(l)

What is the total number of liters of O2(g) at STP needed to produce 6.0 × 1023 molecules of H2O(l)?

A)33.6 L
B)44.8 L
C)11.2 L
D)22.4 L

V = 22.34 L

Explanation:

Given data:

Volume of O₂ needed = ?

Temperature and pressure = standard

Number of molecules of water produced = 6.0× 10²³

Solution:

Chemical equation:

2H₂ + O₂       →      2H₂O

Number of moles of water:

1 mole contain 6.022× 10²³ molecules

6.0× 10²³ molecules ×  1 mole  /  6.022× 10²³ molecules

0.99 mole

Now we will compare the moles of oxygen and water.

                  H₂O         :            O₂  

                    2            :              1

               0.996         :          0.996

Volume of oxygen needed:

PV = nRT

V = nRT/P

V = 0.996 mol × 0.0821 atm.L/mol.K ×  273.15 K / 1 atm

V = 22.34 L

considering the question as per the attachment

here we can see that the radon nuclide has 222 as the atomic mass number and 86 as the atomic number.

when it undergoes nuclear fission it gives polonium which has atomic mass number as 218 and atomic number will be 84 along with a helium nucleus which has 4 atomic mass number and 2 as its atomic number.

222 = 218 + 4 (atomic mass number)

86 = ? + 2; therefore ? = 86-2 = 84.

the atomic mass number of polonium will be 84.