1.386 g of Mg ribbon combusts to form 2.309 g of oxide product. The mass percent of oxygen in the oxide is 40.0 %.
Let's consider the reaction for the combustion of Mg.
Mg + 1/2 O₂ ⇒ MgO
1.386 g of Mg combusts to form 2.309 g of MgO. We want to determine the mass of oxygen in MgO. According to Lavoisier's law of conservation of mass, matter is not created nor destroyed over the course of a chemical reaction. Then, the mass of Mg in the reactants is equal to the mass of Mg in MgO. The mass of the magnesium oxide is the sum of the masses of magnesium and oxygen. The <u>mass of oxygen in the oxide</u> is:

We can calculate the mass percent of O in MgO using the following expression.

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Answer: I would think Europa.
Explanation:
Answer:
Environment A is not undergoing succession, and Environment B is.
Explanation:
Ecological succession is a gradual process in which ecosystems significantly change over time. Ecological succession is a term used by scientists to describe the change in the structure of a community of different species, or ecosystem. This concept of ecological succession stems from a desire to understand the patterns of change in large and complex ecosystems like forests and how they can exist in places known to be recently formed, such as volcanic islands.
In environment A, the ecosystem is not really changing, organisms are merely returning to their natural habitat. It does not represent any change in the ecosystem.
In environment B, the original ecosystem has become grossly modified, first by the appearance of lichen and mosses and subsequently by grasses shrubs and animals. These sequence of events correlate well with the idea of ecological succession presented in the opening paragraph hence environment B is undergoing ecological succession.
<u>Any of five chemical substances that are not metals and that combine with hydrogen to form strong acid compounds from which simple salts can be made</u>