Question

Calculate the amount of heat released in the combustion of 10.9 grams of Al with 3.5 grams of O₂ to form Al₂O₃(s) at 25°C and 1 atm. $\Delta$ ΔH_fAl₂O₃(s) = ­−1676 kJ/mol HINT: What does $\Delta$ ΔH_fAl₂O₃(s) mean?

Enter a positive number since released implies a negative number already. Enter to 1 decimal place in kJ.

Answer 1

long gm Al, melar mass of Al = 27 almal - a moles of Al= 10.9 = 0.4 04 moles 27 3-5 gm or imolar mass of or = 32 g/mol a moles of o2 = 3-5 = o. log moles 24l. + 2 2 6 4102 DHE = -1676 K2 2 1676 kg heat is produced when I mol Alo z is formed. 32 mol los mol on react with a 02 will need Oologx 2 mol al so o log mol = 0.1458 mol al and we have enough Al ) meles of Al, og produced Ix0e70g = 0-0729_ وله m Theat released = 0.0129 81676 122.2 kg