Earth is 1 AU away from the sun. This distance stays nearly the same as Earth revolves around the sun. This is because Earth’s orbit is almost circular. Mercury’s orbit is elliptical. What does this mean in regard to Mercury’s distance from the sun?

a

Mercury follows an irregular path around the sun.

b

Mercury’s distance from the sun is always the same.

c

Mercury travels farther from the sun than Earth does.

d

Mercury’s distance from the sun varies in predictable ways.

Liquid ammonia is produced at high temperatures and under great pressure in a tank by passing a mixture of nitrogen gas and hydrogen gas over an iron catalyst. the reaction is represented by the following equation. n2(g) + 3h2(g) → 2nh3(g) changing all but one experimental condition will affect the amount of ammonia produced. that condition is a) increasing the concentration of both reactants b) changing the temperature within the tank c) decreasing the pressure within the tank. d) increasing only the amount of nitrogen present.