Answer & Explanation:
The reason why is because global fossil fuel consumption is on the rise, and new reserves are becoming harder to find. Those that are discovered are significantly smaller than the ones that have been found in the past.
Oil: Consumption (Predictions): Over 11 Billion tonnes Annually. If we carry on as we are, our known oil deposits could run out in just over 53 years.
Gas (Predictions): If we increase gas production to fill the energy gap left by oil, our known gas reserves only give us just 52 years left.
Coal: Although it’s often claimed that we have enough coal to last hundreds of years, this doesn’t take into account the need for increased production if we run out of oil and gas, our known coal deposits could be gone in 150 years.
For example, oil reserves are a good example: 16 of the 20 largest oil fields in the world have reached peak level production – they’re simply too small to keep up with global demand.
During the year of 2015, fossil fuels made up 81.5% of total U.S. energy consumption. The number is most likely increasing every year.
(fyi: the graph provided is showing future energy reserves for coal, gas and oil. approxiamately.)
Total vapor pressure can be calculated using partial vapor pressures and mole fraction as follows:

Here,
is mole fraction of A,
is mole fraction of B,
is partial pressure of A and
is partial pressure of B.
The mole fraction of A and B are related to each other as follows:

In this problem, A is hexane and B is octane, mole fraction of hexane is given 0.580 thus, mole fraction of octane can be calculated as follows:

Partial pressure of hexane and octane is given 183 mmHg and 59.2 mmHg respectively.
Now, vapor pressure can be calculated as follows:

Putting the values,

Therefore, total vapor pressure over the solution of hexane and octane is 131 mmHg.
Significant figures are numbers that are not 0s, but they are included if they are between two numbers:
There are three significant figures, 304
Hope this helps! :)
The substance should be in liquid state.
First, it takes up space in the container, which leads to that it shouldn't be a solid, because solid doesn't change its shape easily.
Second, it has a fixed volume, it's difficult to compress the substance, therefore it shouldn't be gas too, as gas can be compressed easily.
Therefore we're left with liquid. And both of these given properties fits the property of liquid.
Hello. Although it is not possible to see the video to which the question refers, we can see, in the question, that water is removed from the cylinder as a gas is added to the same cylinder. So we can see that a gas was produced in the reaction, through the displacement of water, that is, if the water starts to be removed from the cylinder, it is because the reaction is producing a gas. If the gas is not produced, water will not come out of the cylinder.