4P + 502 -> P4O10 this is the answer
The coefficient for hydrogen in the balanced equation of solid molybdenum(iV) oxide with gaseous hydrogen is 2
Explanation
Coefficient is defined to as a number in front of a chemical formula in a balanced chemical equation.
The reaction of molybdenum (iv) oxide with gaseous hydrogen is as below,
MoO2 + 2 H2→ Mo +2 H2O
From balanced equation above the coefficient for H2 is 2 since the number in front of H2 is 2
Answer: 0.529 atm
Explanation:
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,

where,
= initial pressure of gas = 0.998 atm
= final pressure of gas = ?
= initial volume of gas = 2 L
= final volume of gas = 3.5 L
= initial temperature of gas = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:


Thus the pressure if it is brought to a higher altitude where it now occupies 3.5 L and is at 12.0 °C is 0.529 atm