The question is incomplete, here is the complete question:
Consider the following reaction: 
In the first 15.0 s of the reaction, 1.9×10⁻² mol of O₂ is produced in a reaction vessel with a volume of 0.480 L . What is the average rate of the reaction over this time interval?
<u>Answer:</u> The average rate of appearance of oxygen gas is 
<u>Explanation:</u>
We are given:
Moles of oxygen gas = 
Volume of solution = 0.480 L
Molarity is calculated by using the equation:

So, 
The given chemical reaction follows:

The average rate of the reaction for appearance of
is given as:
![\text{Average rate of appearance of }O_2=\frac{\Delta [O_2]}{\Delta t}](https://tex.z-dn.net/?f=%5Ctext%7BAverage%20rate%20of%20appearance%20of%20%7DO_2%3D%5Cfrac%7B%5CDelta%20%5BO_2%5D%7D%7B%5CDelta%20t%7D)
Or,

where,
= final concentration of oxygen gas = 0.0396 M
= initial concentration of oxygen gas = 0 M
= final time = 15.0 s
= initial time = 0 s
Putting values in above equation, we get:

Hence, the average rate of appearance of oxygen gas is 
First, we'll balance the equation
C3H8 + 5O2 --> 3CO2 + 4H2O
Next, we know that a gas at stp occupies 22.4 liters/mole, so we can find the number of moles of oxygen gas.
15 liters O2 * (1 mole O2)/(22.4 liters O2) = 0.67 moles O2
Now we know from our balanced equation that there are 3 moles of CO2 per mole of O2, so we can find the number of moles of CO2 we produce.
0.67 moles O2 * (3 moles CO2/5 moles O2) = 0.40 moles CO2
Now, we have the number of moles of CO2, and we know that one mole occupies 22.4 liters, we can find the number of liters
.40 moles CO2 * (22.4 liters CO2)/(1 mole CO2) = 9.0 liters of CO2
The answer is D
Examples: phosphorus trichloride
( PCl3)
Phosphorus trioxide
( P2O3)
Answer:
at summer season the snow will melt and will produce water and using generators we can produce electric energy and in spring and winter can produce electric energy also using the wind
Energy is used by plants to carry cellular respiration.