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OB: OB: to practice and master energy unit conversions, and to include energy into Stoichiometry problems. . Calculators and reference tables now. You eat about 1450 Calories per day. Convert that amount of energy into calories, joules, and kilojoules.
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OB: OB: to practice and master energy unit conversions, and to include energy into Stoichiometry problems. Calculators and reference tables now
You eat about 1450 Calories per day. Convert that amount of energy into calories, joules, and kilojoules.
You eat about 1450 Calories per day. Convert that amount of energy into calories, joules, and kilojoules. 1000 cal 1 C = 1,450,000 calories 1450 C 1 X Keep the 3 SF
= 6,061,000 J = 6,060,000 J with 3 SF 4.18 Joules1 calorie 1,450,000 calories1 x 1 kJ1000 J 6,060,000 J1 X = 6,060 kJ keeping 3 SF
A teaspoon of sugar (sucrose, C12H22O11) has 41 Calories. How many calories, joules and kilojoules is in 2 teaspoons of sugar? A normal amount in a cup of tea or coffee? Show work for all three problems.
How many calories, joules and kilojoules is in 2 teaspoons of sugar? 82 C1 X 1000 cal1 C = 82,000 cal with 2 SF 82,000 cal1 X 4.18 J1 cal = 342,760 J = 340,000 Joules with 2 SF 340,000 J1 X 1 kJ1000 J = 340 kJ with 2 SF
Propane gas, C3H8 combusts according to Table I How much energy (in kilo joules) is released when 5.75 moles C3H8 combusts? Hint: this is a simple mole to mole type stoich problem
Propane gas, C3H8 combusts according to Table I How much energy (in kilo joules) is released when 5.75 moles C3H8 combusts? C3H8 + 5 O2 ---> 3CO2 + 4 H2O ΔH = -2219.2 kJ You need to get right now, that when 1 mole C3H8 combusts that 2219.2 kJ of energy is released (negative ΔH indicates exothermic). You also need to grasp that energy is part of the actual mole ratio. So, C3H8energy 12219.2 kJ 5.75X kJ MR X = 12760.4 kJ X = 12,800 kJ with 3 SF
Last problem for today. How much energy is absorbed by the reaction of 99.0 moles of hydrogen mono-iodide gas forming? (hint, look on table I)
H2(G) + I2(G) ---> 2HI (G) ΔH = +53.0 kJ Which means, when 2 moles HI gas forms, then 53.0 kJ of energy is absorbed. Use the mole ratio to do this problemfor 99.0 moles HI gas. 2X = 5247 kJ X = 2623.5 kJ X = 2620 kJ with 3 SF 253.0 kJ HIenergy 99.0X kJ MR start the diary!