Could you name the acid and alkaline used to make calcium ethanoate please

When the mercury level in a barometer decreases that atmospheric pressure has

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.

The diagram shows the relationship between scientific disciplines.the names of some scientific disciplines have been removed from the boxes. which scientific discipline belongs in the blue box? a.physics b.biology c.chemistry d.metallurgy