<span>Avogadro's number represents the number of units in one mole of any substance. This has the value of 6.022 x 10^23 units / mole. This number can be used to convert the number of atoms or molecules into number of moles. We calculate as follows:

</span>1.40x10^23 molecules of N2 ( 1 mol / 6.022 x 10^23 molecules ) ( 28.02 g / mol ) = 6.51 g N2

7 0

2 years ago

What is the molarity of a solution made by dissolving 68.4g of NaOH in enough water to produce a 875 ml solution?

PilotLPTM [1.2K]

We first calculate for the number of moles of NaOH by dividing the given mass by the molar mass of NaOH which is equal to 40 g/mol. Solving,
moles of NaOH = (68.4 g/ 40 g/mol) = 1.71 moles NaOH
Then, we divide the calculate number of moles by the volume in liters.
molarity = (1.71 moles NaOH / 0.875 L solution)
molarity = 1.95 M

8 0

1 year ago

Which equation represents a reduction half-reaction?

horsena [70]

Answer:

Fe3+ + 3e– --------> Fe

Explanation:

Reduction refers to a gain of electrons. A specie is said to be reduced when it gains electrons or when it experiences a decrease in oxidation number. The both sentences above can be clearly seen when inspecting a reduction half equation.

Consider the redox reaction half equation;

Fe3+ + 3e– ------>Fe

We can see that Fe^3+ accepted three electrons, the oxidation number of iron thereby decreased from +3 to zero from left to right. This implies that the Fe^3+ was actually reduced according to the equation shown.

7 0

2 years ago

Which of the following statements is not true of the combustion of an organic compound?

Novay_Z [31]

<em>The following statements are not true of the combustion of an organic compound is </em>

<em>C. it can also be described as a synthesis reaction </em>

<h3><em>Further explanation</em></h3>

Organic compounds have a characteristic that there is a chain of carbon atoms, while in inorganic does not have a chain of carbon atoms

The reaction of a substance with oxygen is called a combustion reaction

Perfect combustion of carbon compounds will get CO2 gas, whereas if it is not perfect it will produce CO gas

Identification of carbon compounds can usually be done by flowing it into lime water which produces turbid water because of the reaction of CO2 with Ca(OH)₂ to form CaCO₃

Burning organic samples will convert C atoms to CO₂ and H to H₂O

We see the answer choices

1. Oxygen is included in the reactants in the combustion process

So the answer is correct

2. Energy is released during combustion because the reaction is exothermic or releases heat with a negative enthalpy of combustion

So the answer is correct

3. A decomposition reaction is the decomposition reaction of a compound into its constituent elements. In combustion reactions, occur decomposition, not a formation reaction

So the answer is wrong

4. CO₂ is the result of combustion,

So the answer is correct

<h3><em>Learn more</em></h3>

properties of hydrocarbons brainly.com/question/4619751

<h3><em>Answer details </em></h3>

Grade: Senior High School

Subject: Chemistry

Chapter: Hydrocarbons

Keywords: combustion, organic, inorganic, a carbon chain

7 0

2 years ago