Answer:
c. 3
Explanation:
The unbalanced reaction expression is given as:
Fe + O₂ → Fe₂O₃
To balance the expression gives the coefficient of oxygen.
Assign the coefficients a,b, c and use a mathematical approach to solve this problem:
aFe + bO₂ → cFe₂O₃
Conserving Fe: a = 2c
O: 2b = 3c
Now let c = 1, a = 2, b = 
Multiply through by 2,
a = 4, b = 3 and c = 2
4Fe + 3O₂ → 2Fe₂O₃
The coefficient of O₂ is 3
Mol of Kr gas = 1.244
<h3>Further explanation</h3>
In general, the gas equation can be written
<h3> PV=nRT
</h3>
where
P = pressure, atm
V = volume, liter
n = number of moles
R = gas constant = 0.08205 L.atm / mol K
T = temperature, Kelvin
P=1.31 atm
V=23.3 L
T=26+273=299 K
mol of sample :
It changes because when the 2 tectonic plates collide they form mountains and volcanoes.
Continental drift causes tectonic plates to either "pull apart" or "crash" into each other.
Plates that crash into each other either form mountains, or when one slides under the other (a subduction zone) volcanoes from.
Answer:Independent, dependent, and controlled variables.
Explanation:
