What are the 4 indicators that a chemical reaction has taken place? what are they

Liv sheldon given the balanced equation for an organic reaction: c2h2 + 2cl2 → c2h2cl4 this reaction is best classified as *

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

Name a brittle metal , which is used to galvanize iron