An element is just consisted of one type of atom and cannot be broken down by chemicals (Ex. Oxygen just has the oxygen molecule)
A compound is when there's a mixture of atoms and can be broken down by chemicals (Ex. NaCl is made up of sodium and chloride atoms)
Answer:

Explanation:
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In this case, according to the given data, it is possible to infer that the gas mixture lies on the 15.0 cm-high column of water, so that the total pressure or atmospheric pressure is given by:

Thus, since the atmospheric pressure is 745 mmHg and the vapor pressure of water is 18 mmHg, the pressure of hydrogen turns out to be:

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Answer:

Explanation:
Hello there!
In this case, according to the given combustion reaction of octane, it is possible for us to perform the stoichiometric method in order to calculate the mass of octane that is required to consume 300.0 g of oxygen by considering the 2:25 mole ratio, and the molar masses of 114.22 g/mol and 32.00 g/mol respectively:

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Answer:
= 0.030 M
Explanation:
We can take x to be the concentration in mol/L of Ag2SO4 that dissolves
Therefore; concentration of Ag+ is 2x mol/L and that of SO4^2- x mol/L.
Ksp = 1.4 x 10^-5
Ksp = [Ag+]^2 [SO42-]
= (2x)^2(x)
= 4x^3
Thus;
4x^3 = 1.4 x 10^-5
= 0.015 M
molar solubility = 0.015 M
But;
[Ag+]= 2x
Hence; silver ion concentration is
= 2 x 0.015 M
= 0.030 M