I need help with this if anyone can help me I would highly appreciate thank you.

Which metal exist in liquid state and can be cut with knife ?

What is the ph of a 0.0010 m hno3? 1.0 3.0 4.0 5.0

Which of the following describes a compound? (hint: carbon and oxygen bo a. a piece of pure carbon, containing only carbon atoms b. oxygen gas surrounding a solid piece of carbon c. a substance made of two oxygen atoms for each carbon atom carbon and oxygen atoms mixed without being bonded together