The head of a matchstick has a great deal of chemical energy stored in it, including combustible substances that produce a flame when rubbed against a suitable surface. ... As the combustible materials burn, some of the chemical energy is transformed into heat energy, and some is transformed into light energy. Hope this helps
Answer:
Q = 1267720 J
Explanation:
∴ QH2O = mCpΔT
∴ m H2O = 500 g
∴ Cp H2O = 4.186 J/g°C = 4.183 E-3 KJ/g°C
∴ ΔT = 120 - 50 = 70°C
⇒ QH2O = (500 g)(4.183 E-3 KJ/g°C)(70°C) = 146.51 KJ
∴ ΔHv H2O = 40.7 KJ/mol
moles H2O:
∴ mm H2O = 18.015 g/mol
⇒ moles H2O = (500 g)(mol/18.015 g) = 27.548 mol H2O
⇒ ΔHv H2O = (40.7 KJ/mol)(27.548 mol) = 1121.21 KJ
⇒ Qt = 146.51 KJ + 1121.21 KJ = 1267.72 KJ = 1267720 J
1 mole is 6.02x 10^23 molecules
3 * 6.02*10^23 =1.806*10^24 molecules
