Use the Standard Reaction Enthalpies Given Below to Determine $D _ { \mathrm { r } }$

question 145

Multiple Choice

Use the standard reaction enthalpies given below to determine $D _ { \mathrm { r } }$ H° for the following reaction: 2S(s) + 3O₂(g) ? 2SO₃(g) _DrH°= ?
Given:
SO₂(g) ? S(s) + O₂(g) _DrH°= +296.8 kJ
2SO₂(g) + O₂(g) ? 2SO₃(g) _DrH°= -197.8 kJ

• A)-494.6 kJ mol^-1
• B)-692.4 kJ mol^-1
• C)-791.4 kJ mol^-1
• D)1583 kJ mol^-1
• E)-293.0 kJ mol^-1

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Definitions:

Progesterone

A steroid hormone released by the corpus luteum and placenta, playing a key role in the menstrual cycle and maintaining the early stages of pregnancy.

Myometrium

Muscular wall of the uterus; composed of smooth muscle; also called muscular layer.

Trophoblast

The outer layer of cells of a blastocyst, which provides nutrients to the embryo and develops into a large part of the placenta.

HCG

Human chorionic gonadotropin (HCG) is a hormone produced by the placenta after implantation, often used in pregnancy tests.