Hydrazine, N 2 H 4 , once used as a rocket propellant, reacts with oxygen: N 2 H 4 + O 2 → N 2 + 2 H 2 O (a) How many grams of O2 are needed to react with 50.0 g of N 2 H 4 ?

Alright folks, so we have a balanced reaction below here that shows the combustion of propane. Right? So we have propane combusting with oxygen producing C. 02 and water. So if we're told that we have 132 point grams of C three H eight of propane, that's completely combusted. We need to calculate the mass in grams of oxygen needed for this process. So we want Massive oxygen given the mass of propane. Okay, so let's go ahead and start. So we already told that this is a balanced reaction. So we don't need to check. But you can go ahead and check anyways, it is balanced and we are ready to start. So 132.1 grams of propane. That's what we're going to start with. Because that's the only thing that we have given to us that we know. And we're gonna go ahead and convert this into moles so that we can do a multiple comparison between propane and oxygen to find uh the mass of 02. Alright, so in one mole of propane, how many grams do we have? That is just the molar mass of propane. Let's go ahead and find that on the side. So we have carbon and hydrogen For the carbon, we have three of them. Right? And each of them weigh 12. So that gives us 36 Gramps. And then for the hydrogen is we have eight of them. They weigh 1.01 each. So that is 8.08 g. And then in total, this will be 44.08 grams Permal. So that's the molar mass of propane. So we're going to put that on the bottom. So 44.08 grams of C three H eight In one mole of it. Okay, so g cancel out. And now we have moles. Now we can do a multiple comparison, right? So we can see that there is only one mole of propane. We're going to put that on the bottom so that it can cancel out. So for every one mole of propane we're using five moles of 02. So moles of O to go on the top because that's what we want. Right? So now that we have moles of 02, we can very easily convert that into grams right into mass and grams. So again, we just need the molar mass of 02. So in one mole of 02 and moles of O. To go on the bottom. So that we can cancel that out. How many grams are there? Well as oxygen, it's 16 g. Right? There's two of them. 16 times two is 32. So there are 32 g of 02 in one mole of 02. So moles cancel out and now we have grams of 02. And that will be our answer. So let's go ahead and divide and multiply everything correctly here. And it should give you 479.5 g of co two. Alright, so that's gonna be our answer for the mass and grams of CO. Two needed for this combustion reaction. Thank you so much for watching.

Ch.3 - Mass Relationships in Chemical Reactions

All textbooks

McMurry 8th Edition

Ch.3 - Mass Relationships in Chemical Reactions

Problem 73a

Chapter 3, Problem 73a

Hydrazine, N₂H₄, once used as a rocket propellant, reacts with oxygen: N₂H₄ + O₂ → N₂ + 2 H₂O (a) How many grams of O2 are needed to react with 50.0 g of N₂H₄?

Verified step by step guidance

Determine the molar mass of N_2H_4 by adding the atomic masses of nitrogen and hydrogen.

Calculate the number of moles of N_2H_4 using the given mass (50.0 g) and its molar mass.

Use the balanced chemical equation to find the mole ratio between N_2H_4 and O_2.

Calculate the number of moles of O_2 needed using the mole ratio from the balanced equation.

Determine the mass of O_2 required by multiplying the moles of O_2 by its molar mass.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.

Video duration:

Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Stoichiometry

Stoichiometry is the branch of chemistry that deals with the quantitative relationships between the reactants and products in a chemical reaction. It allows chemists to calculate how much of each substance is needed or produced based on balanced chemical equations. In this case, understanding the stoichiometric coefficients from the reaction equation is essential to determine the amount of O2 required for the reaction with a given mass of N2H4.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is crucial for converting between the mass of a substance and the number of moles, which is necessary for stoichiometric calculations. For this problem, calculating the molar mass of N2H4 and O2 will enable the conversion of grams to moles, facilitating the determination of the required amount of O2.

Balanced Chemical Equation

A balanced chemical equation represents a chemical reaction with equal numbers of each type of atom on both sides of the equation. It ensures the law of conservation of mass is upheld. In this scenario, the balanced equation N2H4 + O2 → N2 + 2 H2O provides the necessary ratios of reactants and products, which are essential for calculating the amount of O2 needed to react with a specific mass of N2H4.

Recommended video:

Guided course

01:32

Balancing Chemical Equations

Related Practice

Textbook Question

An alternative method for producing hydriodic acid is the reaction of iodine with hydrogen sulfide:H₂S + I₂ → 2 HI + S (b) How many grams of HI are produced from the reaction of 95.4 g of H₂S with excess I₂?

461

views

Textbook Question

Nickel(II) sulfate, used for nickel plating, is prepared by treat-ment of nickel(II) carbonate with sulfuric acid: NiCO₃ + H₂SO₄ → NiSO₄ + CO₂ + H₂O (a) How many grams of H₂SO₄ are needed to react with 14.5 g of NiCO₃?

1044

views

Textbook Question

Nickel(II) sulfate, used for nickel plating, is prepared by treat-ment of nickel(II) carbonate with sulfuric acid: NiCO₃ + H₂SO₄ → NiSO₄ + CO₂ + H₂O

(b) How many grams of NiSO4 are obtained if the yield is 78.9%?

962

views

Textbook Question

Hydrazine, N₂H₄, once used as a rocket propellant, reacts with oxygen: N₂H₄ + O₂ → N₂ + 2 H₂O (b) How many grams of N₂ are obtained if the yield is 85.5%?

1310

views

Textbook Question

Assume that you have 1.39 mol of H2 and 3.44 mol of N2. How many grams of ammonia (NH3) can you make, and how many grams of which reactant will be left over?3 H2 + N2 --> NH3

1404

views

Textbook Question

Hydrogen and chlorine react to yield hydrogen chloride: H2 + Cl2 ¡ 2 HCl. How many grams of HCl are formed from reaction of 3.56 g of H2 with 8.94 g of Cl2? Which reactant is limiting?

2471

views

Hydrazine, N2H4, once used as a rocket propellant, reacts with oxygen: N2H4 + O2 → N2 + 2 H2O (a) How many grams of O2 are needed to react with 50.0 g of N2H4?

Verified video answer for a similar problem:

Key Concepts

Stoichiometry

Molar Mass

Balanced Chemical Equation

Hydrazine, N₂H₄, once used as a rocket propellant, reacts with oxygen: N₂H₄ + O₂ → N₂ + 2 H₂O (a) How many grams of O2 are needed to react with 50.0 g of N₂H₄?