A teacher has found two white powders on a desk in the chemistry laboratory. she wants to test to see if they are pure substances, so she measures the melting points. substance X melts at 122 and substance Y melts between 87 and 93. explain which one is a pure substance

Mitosis is a type of cell division that produces cells that are identical to the parent cell. meiosis is a different type of cell division that produces cells that carry have a genetic material of the parent cell. based on the information provided how do the purpose of mitosis and meiosis differ

Compare and contrast physical changes with chemical changes.

Identify arrows pointing to bonding electrons. done h-0-0-h ) intro