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.

You can learn more about mass percent here: brainly.com/question/14990953
Electrons and protons, but not neutrons.
Answer:
Explanation:
x in (-oo:+oo)
2 < (1/2)*x-3 // - (1/2)*x-3
2-((1/2)*x)+3 < 0
(-1/2)*x+2+3 < 0
5-1/2*x < 0 // - 5
-1/2*x < -5 // : -1/2
x > -5/(-1/2)
x > 10
x in (10:+oo)
(10:+oo)
1) Only if new observations led to a change in our current knowledge.
2) <span>place their own moral views about the needs of society
3) FALSE
4) FALSE
5) FALSE(i think)
6) TRUE
7) Distillation
8) the # of neutrons
9) the element becomes a different element
10) atomic radii increase
11) decreases
i hope these are right and helps. please give me brainliest</span>
For a solar eclipse t occur;
C. The moon is located from a line between the sun and earth