The value of ΔH° for the reaction below is +128.1 kJ: CH₃OH (l) → CO (g) + 2H₂ (g)
How many kJ of heat are consumed when 15.5 g of C OH (l) decomposes as shown in the equation?

Question

The value of ΔH° for the reaction below is +128.1 kJ: CH₃OH (l) → CO (g) + 2H₂ (g)
How many kJ of heat are consumed when 15.5 g of C

The value of ΔH° for the reaction below is +128.1 kJ: CH<sub>3</sub>OH (l) → CO (g) + 2H<sub>2</sub> (g) How many kJ of heat are consumed when 15.5 g of C OH (l) decomposes as shown in the equation? A) 0.48 kJ B) 62.0 kJ C) 1.3 × 10<sup>2</sup> kJ D) 32 kJ E) 8.3 kJ

OH (l) decomposes as shown in the equation?

Quizplus · Accepted Answer

Step 1: Calculate the moles of C11H24O in 15.5 g:

15.5 g / 170.3 g/mol = 0.091 mol C11H24O

Step 2: Use stoichiometry to calculate the amount of heat consumed:

0.091 mol C11H24O x (128.1 kJ / 1 mol) = 11.63 kJ

Rounded to two significant figures, the answer is 12 kJ. The closest option is B (62 kJ), which can be eliminated because it is too large. The correct answer is A (0.48 kJ), which is obtained by rounding 11.63 kJ to the nearest tenth of a kJ.

The Value of ΔH° for the Reaction Below Is +128