Answer:

Explanation:
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In this case, we can identify the solution to this problem via the Dalton's rule because the partial pressure of helium is given by:

Whereas the mole fraction of helium is calculated by firstly obtaining the moles and then the mole fraction:

Then, we calculate the partial pressure as shown below:

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Answer: Manholes are usually round, primarily because roundness is the best shape to resist the compression of the earth; covers are round because they are easier to manufacture than square or rectangular shapes, they are easier to move by rolling, and they can't fall into the opening.
Explanation:
Non-metal atoms gain an electron, or electrons, from another atom to become >negatively charged ions.
Answer:
A) The mass would be the same.
Explanation:
Since there is no loss of any particle to vapor during the phase change process from solid to liquid, the mass of the before and after the process will remain the same.
- In this way, the law of conservation of mass is obeyed.
- Mass is the amount of matter contained in a substance.
- Since there is no room for escape or matter loss, the mass will remain the same.
The reaction will generally form more reactants than products.