Answer:
1) The correct step in the scientific method that Victor did is Construct a hypothesis.
2) Given mass and density, volume is calculated as mass divided by density.
Explanation:
1) Before doing the assay and make a graph with the results obtained, Victor should think what he wants to prove, so he should make a hypoythesis to test with the assay.
2) The formula of density is
density = mass/volume ⇒ density x volume = mass ⇒ volume = mass/density.
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
Answer:
Contributes to the membrane potential.
Explanation:
Sodium-potassium pump: In cellular physiology, a protein which is identified in many cells that helping in to maintain the higher concentration of potassium ions inside than that is in the surrounding medium and maintain the lower concentration of sodium ions inside than that of the surrounding medium.
This unbalanced charge transfer contributes in the separation of charge across the cell membrane. Sodium-potassium pump is known for important contributor to action potential which is produce by nerve cells.
The most appropriate answer is C !!
Aqua regia is an oxidative mixture that is highly corrosive and is composed of hydrochloric acid and nitric acid. The Ea (rev) for the reaction is 3 kJ.
<h3>What is activation energy?</h3>
The activation energy is the minimum required energy by the reactant to undergo changes to form the product. The activation energy of the reverse reaction is given by the difference in the production state and transition state.
It is given as,
Ea (rev) = Ea (fwd) − ΔHrxn
Given,
ΔH° = 83KJ
Ea (fwd) = 86 kJ/mol
Substituting the values above as:
Ea (rev) = 86 - 83
= 3 kJ
Therefore, the activation energy of the reverse reaction is 3 kJ.
Learn more about activation energy, here:
brainly.com/question/14287952
#SPJ4