7. If the heat of formation of sodium chlorate is –53 kJ/mol, then the heat of reaction for 3.5 mol of sodium chlorate isa. –17.7 kJ d. 159 kJb. 17.7 kJ e. none of the abovec. –185.5 kJ

If it takes 41.72 joules of heat for a piece of gold weighing 18.69 grams from 10.0oC to 27.0oC, what is the specific heat of the gold?

3. A certain quantity of nitrous oxide (laughing gas) expands, doing 144 J of work. At the same time, it absorbs 299 J of heat from the surroundings. Which ONE represents the change in internal energy of the nitrous oxide? A. B. C. D. E. -443 J -155 J OJ 155 J 443 J

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3. Suppose the 25.0 g of the following substances all initially at 27.0 °C absorb 2.35 kJ of energy. What is the final temperature of each? D) Water.  You will need to look up specific heat values.

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

When 25.0 g hydrogen gas react according to the following reaction, how many kJ of heat are released or consumed? CO (g)    +   3 H2 (g)   -->   CH4 (g)   +   H2O (g)      Delta Hrxn =  – 206 kJ a. – 1.28 x 103 J b. – 25.5 J c. – 639 J d. – 2.55 x 103 J e. – 1.29 x 103 J f. none of these