Melted rock can ooze out from below the earth's surface through a crack called a fault.
Answer:
The molecular formula of the compound :
Explanation:
The empirical formula of the compound =
The molecular formula of the compound =
The equation used to calculate the valency is :

We are given:
Mass of molecular formula = 86 g/mol
Mass of empirical formula = 43 g/mol
Putting values in above equation, we get:

The molecular formula of the compound :

Answer:
This means that the isotope of silicon with a mass number of 28 is by far the most common of these three isotopes.
Explanation:
The abundance of Si-28 is 92.23%. Si-29 is 4.68% and Si-30 is 3.09%.
Because most Si atoms have a mass of 28 amu, the average mass of all silicon atoms is very close to 28.
Here is a video which summarizes how to calculate average atomic mass from data about mass and relative abundance.
Answer:

Explanation:
Hello there!
In this case, according to the given information, it turns out possible to set up the following energy equation for both objects 1 and 2:

In terms of mass, specific heat and temperature change is:

Now, solve for the final temperature, as follows:

Then, plug in the masses, specific heat and temperatures to obtain:

Yet, the values do not seem to have been given correctly in the problem, so it'll be convenient for you to recheck them.
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