For which of the following activities might you want to hire a chemist?
Answer: D. testing a rock sample for gold content
Which of the following procedures involves a physical change in one of the substances?
Answer: C. separating a salt solution by evaporating the water
C. both a and b
If a light bulb can last longer with the same amount of energy it is given, that means it can use less energy to do the same job compared to one that does not last longer with the same amount of energy it is given. It is much like how a more fuel efficient car will be able to go farther on the same tank of gas, but if you pair it with a car that doesn't have as great of an mpg, when they go the same distance, the car with the greater mpg spends less fuel.
If you don't have to use the energy when you aren't utilizing it, then you can conserve the energy for when you do need it.
The pressure exerted when both gases are put together in a single 1 liter container is 5 atm.
<h3>What is pressure?</h3>
Pressure is the force exerted by any object on another object.
Given that, a and b separate 1 liter containers and exert pressure of 2 atm and 3 atm respectively.
When both gases a and b exert together, the pressure then
2 atm + 3 atm = 5 atm.
Thus, the pressure exerted when both gases are put together in a single 1 liter container is 5 atm.
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Answer: The early atmosphere
Explanation: Its early atmosphere was probably formed from the gases given out by volcanoes. It is believed that there was intense volcanic activity for the first billion years of the Earth's existence. The early atmosphere was probably mostly carbon dioxide, with little or no oxygen.
