The overall reaction in a commercial heat pack can be repre- sented as 4Fe(s) + 30₂(g) 2Fe₂O3(s) ΔΗ = - 1652 kJ a. How much heat is released when 4.00 mol iron is reacted with excess O₂? b. How much heat is released when 1.00 mol Fe₂O3 is produced? c. How much heat is released when 1.00 g iron is reacted with excess O₂? d. How much heat is released when 10.0 g Fe and 2.00 g O₂ are reacted?

In the following reaction, how much heat is generated when 3.21 moles of CH4 are burned? CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O(g) AH° = -802 kJ/mol

A chemist measures the energy change AH during the following reaction: 2 H₂O(l) → 2 H₂(g) + O₂(g) ΔΗ= 572. kJ Use the information to answer the following questions. This reaction is... Suppose 64.5 g of H₂O react. Will any heat be released or absorbed? If you said heat will be released or absorbed in the second part of this question, calculate how much heat will be released or absorbed. Round your answer to 3 significant digits. O endothermic. O exothermic. O Yes, absorbed. O Yes, released. O No. 0 kJ x10 Start over

6. Calculate the amount of heat released when 1.26 x 104 grams of ammonia NH3 are produced according to the following equation. N₂ + 3H₂ → 2NH3 AH = -92.6 kJ

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q represents the change in heat of a reaction or substance. The units of q are Joules (J) or kilojoules (kJ). For a well understood substance, we can calculate the specific heat which relates the mass of the substance in grams to the amount of heat in J required to raise that amount a certain temperature.  We call that specific heat.  The specific heat (Cs) of water is stated in the following way:  C s ( H 2 O ) = 4.186 J g ∘ C This means that it takes 4.186 J of energy to raise the temperature of 1g of water by 1ºC.  The relationship between q and Cs for a given substance is  where m is mass (g) and ∆T is the change in temperature in ºC (final temp - initial temp).  Calculate the heat change (q) in J when 4.297 grams of water is cooled from 3.967 ºC to -2.902 ºC. Enter your answer with one decimal place (tenths).  Pay careful attention to the sign of your answer.  The sign of ∆T is always the same as the sign for q.

F HNO3 (1 mole) H2SO4, heat ?

A 5.43 g sample of an unknown salt (MM = 116.82 g/mol) is dissolved in 150.00 g water in a coffee cup calorimeter. Before placing the sample in the water, the temperature of the salt and water is 23.72°C. After the salt has completely dissolved, the temperature of the solution is 28.54°C. If -3.13 x 10 J of heat was lost during the dissolution reaction of 0.0465 moles of the unknown salt, what is the enthalpy change (in kJ/mol of salt) for the dissolution reaction? Type here to search

The overall reaction in commercial heat packs can be represented as 4Fe(s) + 302(g) →2Fe₂O3 (8) AH = -1652 kJ a. How much heat is released when 2.20 mol iron is reacted with excess O₂? kl released b. How much heat is released when 1.83 mol Fe2O3 is produced? kJ released c. How much heat is released when 2.20 g iron is reacted with excess O₂? kJ released d. How much heat is released when 11.8 g Fe and 2.61 g O2 are reacted? Submit Answer [Review Topics] kl released Retry Entire Group [References] 8 more group attempts remaining

How much heat is released when 22.75 g oxygen gas is used in the reaction? (Pay close attention to the units your given is in! Maybe need a conversion first?)   4 Fe+ 3 O2 → 2 Fe2O3   ΔH = -1652 kJ