Is it possible for a reaction to be exothermic but not spontaneous?

Match each object to its description: a. coma of a comet b. comet tail c. oort cloud haze surrounding a nucleus created by solar wind. hypothetical sphere around the solar system

Base your answer on the information below and on your knowledge of chemistry. nitrogen dioxide, no2, is a dark brown gas that is used to make nitric acid and to bleach flour. nitrogen dioxide has a boiling point of 294 k at 101.3 kpa. in a rigid cylinder with a movable piston, nitrogen dioxide can be in equilibrium with colorless dinitrogen tetroxide, n2o4. this equilibrium is represented by the equation below. 2no2(g) n2o4(g) + 58kj at standard pressure, compare the strength of intermolecular forces in no2(g) to the strength of intermolecular forces in n2(g).

Asa choose the correct set of reaction coefficients to properly balance the following chemical equation according to the law of conservation of mass: __s8 + __o2 ==> __so2 1, 1, 8 1, 8, 1 1, 8, 8 8, 1, 1