Which element is used in light bulbs?

What is the atomic number of hydrogen?

Which gas do plants absorb during photosynthesis?

What is NaCl commonly known as?

What is the pH of pure water?

What is the most abundant gas in Earth’s atmosphere?

Which acid is found in the stomach?

Which metal is most commonly used in electrical wiring?

Which gas is known as laughing gas?

Which element is used in pencils?