Substance A is tested to see if it is an acid or a base. A piece of iron is placed in substance A and the iron starts to wear away over time (corrosive).
Substance A has a sour taste, and will produce a burning/tingling feeling
when touched with a bare hand. Is Substance A an acid or a base?

Before it was launched, a helium-filled balloon had a pressure of 201 kpa at a temperature of 27°c. at an altitude of 15,000 m, the pressure had decreased to 2.5 kpa and the temperature had dropped to -14 °c. the volume of the balloon increased to 59.3 m3. what is the original volume of the balloon? 13 m3 0.85 m3 0.077 m3 1.17 m3