Answer:
The answer to your question is: A) temperature at which a material catches on fire.
Explanation:
(A) temperature at which a material catches on fire this is a chemical property, so this is the right answer to your question.
(B) color physical property
(C) conductivity physical property
(D) hardness physical property
In chemistry, if you want to express the amount of a substance out of the total amount, you express it in concentration. There are numerous units of measurement: molarity, molality, normality, mass percentages, volume percentage, or a mix of both. For this problem, the unit used for concentration is in mass percentages. The formula would be
Percentage Concentration = [(Actual Amount of Substance)/(Total amount of all substances)] * 100
Since we are given with the total mass of all the substances in the ocean and the percentage concentration, the only missing information is the actual amount of Na+ in the ocean. Substituting the values:
1.076 = (Amount of Na+ /1.8×10²¹ kg)*100
Amount of Na+ = 1.9368×10¹⁹ kg
Answer:

Explanation:
Hello!
In this case, since these calorimetry problems are characterized by the fact that the calorimeter absorbs the heat released by the combustion of the substance, we can write:

Thus, given the temperature change and the total heat capacity, we obtain the following total heat of reaction:

Now, by dividing by the moles in 1.04 g of cyclopropane (42.09 g/mol) we obtain the enthalpy of combustion of this fuel:

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I believe the answer would be Oratorio it was a concert piece not a musical theatre
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.