Answer:
This is an example of a food chain
Explanation:
Think of it as a chain reaction. The grass feeds and nourishes the prairie dog. Upon eating the prairie dog, the coyote gets the nutrients from both the grass the prairie dog ate and from the prairie dog itself.
group 1 elements are metals with<u> low</u> density
Here we have to get the 
of the reaction at 520 K temperature.
The of the reaction is 1.705 atm
We know the relation between and 
is 
, where = The equilibrium constant of the reaction in terms of partial pressure, = The equilibrium constant of the reaction in terms of concentration and N = number of moles of gaseous products - Number of moles of gaseous reactants.
Now in this reaction, PCl₃ + Cl₂ ⇄ PCl₅
Thus number of moles of gaseous product is 1, and number of moles of gaseous reactants are 2. Thus N = |1 - 2| = 1 mole
The given value of is 4.0×10⁻²
The molar gas constant, R = 0.082 L. Atm. mol⁻¹. K⁻¹ and temperature, T = 520 K.
On plugging the values in the equation we get,
Or, = 1.705 atm
Thus, the of the reaction is 1.705 atm
Molar mass of empirical formula = 172.8 g/mole
346.6g/172.8 g/mole = 2.00 moles
Molecular formula = C2H2Br4
