Which of the following is an example of an ionic compound? co2 nacl na o3

Which of the following would be an accurate picture of the earth during the summer time of the northern hemisphere?

How is the way a mixture is combined different from how a compound is combined?

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