The given question is incomplete. The complete question is :
Gaseous butane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water . If 1.31g of water is produced from the reaction of 4.65g of butane and 10.8g of oxygen gas, calculate the percent yield of water. Be sure your answer has the correct number of significant digits in it.
Answer: 28.0 %
Explanation:
To calculate the moles :


According to stoichiometry :
13 moles of
require 2 moles of butane
Thus 0.34 moles of
will require=
of butane
Thus
is the limiting reagent as it limits the formation of product and butane is the excess reagent.
As 13 moles of
give = 10 moles of 
Thus 0.34 moles of
give =
of 
Mass of 


The percent yield of water is 28.0 %
1.25 moles is the answer
But I hope I really help
Answer:
Its pressure will be 0.54 atm at 100 K.
Explanation:
Gay-Lussac's law indicates that, as long as the volume of the container containing the gas is constant, as the temperature increases, the gas molecules move faster. Then the number of collisions with the walls increases, that is, the pressure increases. That is, the pressure of the gas is directly proportional to its temperature.
Gay-Lussac's law can be expressed mathematically as the quotient between pressure and temperature equal to a constant:

Studying two different states, an initial state 1 and a final state 2, it is satisfied:

In this case:
- P1= 1.75 atm
- T1= 50 °C= 323 K (being 0 C=273 K)
- P2= ?
- T2= 100 K
Replacing:

Solving:

P2= 0.54 atm
<u><em>Its pressure will be 0.54 atm at 100 K.</em></u>
Answer:- 6984 kJ of heat is produced.
Solution:- From given information, 1367 kJ of heat is produced by the combustion of 1 mole of ethanol. We are asked to calculate the heat produced by the combustion of 235.0 g of ethanol.
Let's convert given grams to moles and multiply by the heat produced by one mole of ethanol to get the total heat produced. Molar mass of ethanol is 46 grams per mole. The set will be:

= 6984 kJ
So, 6984 kJ of heat is produced by the combustion of 235.0 g of liquid ethanol.