Q: What is the term for an ionic compound that produces positive hydrogen ions when dissolved in water? Choices: - hydrocarbon - sulfur - base - acid A:
acid

Q: The motion of stars in galaxies imply that there is about 10 times as much what as in the luminous objects we can see? Choices: - density - heat - light - mass A:
mass

Q: Q: Iridescent green beetles, known as jewel beetles, change color because of the light-reflecting properties of the cells that make up this? Choices: - their hairs - their wings - their scales - their external skeleton A:
A: their external skeleton

Question: Q: The last two stages of aerobic respiration require what? Choices: - water - carbon - sulfur - oxygen A:
Answer: oxygen

*Question*
Q: The fundamental unit of time, the second, is based on what type of clock? Choices: - quantum clock - eternal clock - gravity clock - atomic clock A:
**Answer**
atomic clock

*Question*
Q: What type of metal is a good conductor of electricity? Choices: - Tin - Aluminium - zinc - copper A:
**Answer**
copper