1. 2. Portable hot packs are available for skiers and other people engaged in ot
ID: 997607 • Letter: 1
Question
1.
2.
Portable hot packs are available for skiers and other people engaged in other outdoor activities in a cold climate. The air-permeable paper packet contains a mixture of powdered iron, sodium chloride, and other components, all moistened by a little water. The exothermic iron, sodium chloride, and other components,al moistened by a ittle water The exothermic reaction that produces the heat is a very common one, the rusting of iron: 4Fe(s) + 302 (g) 2Fe 203(s) When the outside plastic envelope is removed, O2 molecules penetrate the paper, causing the reaction to begin. A typical packet contains 250 g of iron to warm your hands or feet for up to 4 hours. How much heat (in kJ) is produced by this reaction? × 10 kJ(Enter your answer in scientific notation.)Explanation / Answer
1)The reaction is the following:
4Fe(s) + 3O2(g)----> 2Fe2O3(s) H = -1,652 KJ
It means that 4 moles of Fe produce 1,652KJ.
In
We need to know the moles of Fe:
Moles of Fe= mass(g)/molar mass = 250g/55.85g/mol = 4.48moles Fe
From the reaction we know that foor moles of Iron liberates 1,652KJ , Then let`s calculate the produced heat by 4.48moles:
Produced heat = 4.48molesFe(1,652KJ/4moles Fe)= 1,850KJ
In scientific notation: Produced heat = 1.85x10-3KJ
2) The smallest atom in group 6A of the periodic table is Oxygen.
In 6A group : O,S,Se,Te,Po.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.