Enthalpy Question URGENT?

Question

Somebody please answer the second question!

N2H4 (g) + O2 (g) --> N2 (g) + 2H20 (I) Delta H=-628 KJ

How many grams of Hydrazine (N2H4) would be required to produce 963 KJ of heat?

If the reaction was at standard temperature and pressure, how many liters of N2 gas would evolve if the amount of N2H4 found in part (a) was burned?

Answer 1

1 mol of any gas at STP occupies 22.4dm3

First, find the mass if Hydrazine.
Ratio of Hydrazine to Nitrogen is 1:1, so for every mol of Hydrazine, there will be one mol of Nitrogen.
Find number of moles in Hydrazine and thus solve volume.

I believe that insufficient information is given for this question to be answered so here is an example.

**NOTE: This example is non-realistic figures***

5g N2H4 produces 963KJ

RMM of N2H4 = 14x2 + 1x4 = 28 + 4 = 32

32g N2H4 = 1 mol
5g N2H4 = 1/32 x 5 = 0.15625 mol

Ratio of N2H4: N2 = 1:1 = 0.15625:0.15625

Therefore, 0.15625 mol of N2 is evolved.

1 mol of any gas occupies 22.4dm3 at STP
0.15625 mol N2 occupies 22.4 x 0.15625 = 3.5dm3

1dm3 = 1000cm3 = 1L
3.5dm3 = 3.5L



Use this example to solve your problem.

Answer 2

i anticipate deltaH is expressed as KJ in line with mole. The destructive sign shows the reaction releases power (Exothermic) Divide 1000 g of U by utilizing its molecular mass, then multiply it by utilizing the deltaH, the consequence would be destructive indicating a launch of warmth by utilizing the reaction. Now, divide 963 KJ by utilizing 628 KJ/mole. you will get the moles of hydrazine necessary. Multiply by utilizing hydrazine molecular weight and you gets the mass of hydrazine necessary. finally, use the suited gas regulation to estimate the quantity of N2 made from the undeniable fact that moles of N2 = moles of Hydrazine. there will be a help in the quantity because of fact there will be a million/2 of moles of gas than initially, yet it extremely is a various tale.

Answer 3

This question has already been answered. You must put some effort on your side, otherwise you will learn nothing. Come on, you can do it.