Answer:
A change is called irreversible if it cannot be changed back again. In an irreversible change, new materials are always formed.
Explanation:
The empirical formula for the compound is - P₂O₅
the empirical formula is the simplest ratio of whole numbers of components in a compound.
molecular formula is the actual ratio of components in a compound.
we have to first find the number of empirical units in the molecular formula
molecular mass - 283.89 g/mol
mass of empirical formula - 283.8 g
number of empirical units - 283.89 g/mol / 283.8 g
number of empirical units - 1.000
therefore empirical formula = molecular formula
molecular formula - P₂O₅
The given question is incomplete. The complete question is:
The change in entropy is related to the change in the number of moles of gas molecules. Determine the change in moles of gas for each of the reactions and decide if the entropy increases decreases or has little to no change:
A. 
B. 
C. 
D. 
Answer: A. : decreases
B. 
: decreases
C. : no change
D. : increases
Explanation:
Entropy is defined as the randomness of the system.
Entropy is said to increase when the randomness of the system increase, is said to decrease when the randomness of the system decrease and is said to have no change when the randomness remains same.
In reaction , as gaseous reactant is changed to solid product, entropy decreases.
In reaction , as 4 moles of gaseous reactants is changed to 2 moles of gaseous product, entropy decreases.
In reaction , as 3 moles of gaseous reactants is changed to 3 moles of gaseous product, entropy has no change.
In reaction , as 1 mole of gaseous reactant is changed to 3 moles of gaseous product, entropy increases.
A
not every expirement has control
