Answer: The final temperature in Kelvin is 1488
Explanation:
To calculate the final temperature of the system, we use the equation given by Gay-Lussac Law. This law states that pressure of the gas is directly proportional to the temperature of the gas at constant pressure.
Mathematically,

where,
are the initial pressure and temperature of the gas.
are the final pressure and temperature of the gas.
We are given:

Putting values in above equation, we get:

Hence, the final temperature in Kelvin is 1488
We know it’s C because of what it says in the text
Answer:
Pyrite.
Explanation:
In this case, for the given samples, we compute the densities considering that the volume of each sample is computed by the difference between the volume of the water + sample and the volume of water:

Therefore, since the density of the samples are closer to the density of pyrite (5.01 g/cm³) we conclude that the samples are more like to be pyrite.
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Answer:
Lithium oxide, Li₂O.
Explanation:
Hello!
In this case, according to the given amounts, it is possible to write down the chemical reaction as shown below:
Which means that the metallic oxide has the following formula: M₂O. Next, we can set up the following proportional factors according to the chemical reaction:
Thus, we perform the operations in order to obtain:
So we solve for x as shown below:
Whose molar mass corresponds to lithium, and therefore, the metallic oxide is lithium oxide, Li₂O.
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