Is it correct to say that the smaller the moles of reactants the greater the heat of combustion in the reaction? Please give me a reference I could read related to this.

9.58 For the reaction C2H2(g)+2H2(g)C2H6,H=136 kJ. What are the ratios that can be defined between moles of substances and energy?

9.89 A sample of gas is 80.0% CH4 and 20.0% C2H6 by mass. What is the heat from the combustion of 1.00 g of this mixture? Assume the products are CO2 (g) and H2O (l).

Why is it important to give the states of the reactants and products when giving an equation for H?

The thermite reaction combines aluminum powder and iron oxide and ignites the mixture to make aluminum oxide and iron. So much energy is given off that the iron productfrequently is molten. Write a balanced chemical reaction for the thermite process and determine its H(25C).

Enthalpy a A 100.-g sample of water is placed in an insulated container and allowed to come to room temperature at 21C. To heat the water sample to 41C, how much heat must you add to it? b Consider the hypothetical reaction,2X(aq)+Y(l)X2Y(aq)being run in an insulated container that contains 100. g of solution. If the temperature of the solution changes from 21C to 31C, how much heat does the chemical reaction produce? How does this answer compare with that in part a? (You can assume that this solution is so dilute that it has the same heat capacity as pure water.) c If you wanted the temperature of 100. g of this solution to increase from 21C to 51C, how much heat would you have to add to it? (Try to answer this question without using a formula.) d If you had added 0.02 mol of X and 0.01 mol of Y to form the solution in part b, how many moles of X and Y would you need to bring about the temperature change described in part c. e Judging on the basis of your answers so far, what is the enthalpy of the reaction 2X(aq) + Y(l) X2Y(aq)?

When one mole of ethylene gas, C2H4, reacts with fluorine gas, hydrogen fluoride and carbon tetrafluoride gases are formed and 2496.7 kJ of heat are given off. What is Hf for CF4(g)?

Consider the following reaction in the vessel described in Question 57. A(g)+B(g)C(s)For this reaction, E=286 J, the piston moves up and the system absorbs 388 J of heat from its surroundings. (a) Is work done by the system? (b) How much work?

A rebreathing gas mask contains potassium superoxide, KO2, which reacts with moisture in the breath to give oxygen. 4KO2(s)+2H2O(l)4KOH(s)+3O2(g) Estimate the grams of potassium superoxide required to supply a persons oxygen needs for one hour. Assume a person requires 1.00 102 kcal of energy for this time period. Further assume that this energy can be equated to the heat of combustion of a quantity of glucose, C6H12O6, to CO2(g) and H2O(l). From the amount of glucose required to give 1.00 102 kcal of heat, calculate the amount of oxygen consumed and hence the amount of KO2 required. The ff0 for glucose(s) is 1273 kJ/mol.

A lead ore, galena, consisting mainly of lead(II) sulfide, is the principal source of lead. To obtain the lead, the ore is first heated in the air to form lead oxide. PbS(s)+32 O2(g)PbO(s)+SO2(g)H=415.4kJ The oxide is then reduced to metal with carbon. PbO(s)+C(s)Pb(s)+CO(g)H=+108.5kJCalculate H for the reaction of one mole of lead(II) sulfide with oxygen and carbon, forming lead, sulfur dioxide, and carbon monoxide.