Classify each process as either physical or a chemical change.

What causes different colors to appear in the sky? the absorption of light by air molecules the reflection of light by bodies of water the greenhouse effect in earth's atmosphere the scattering and reflection of light by dust particles

If an atom has 12 protons and 13 neutrons

Drag the tiles to the correct locations. each tile can be used more than once, but not all tiles will be used. one or more locations will remain empty. nitrosyl fluoride has the chemical formula nof nitrogen has five valence electrons, oxygen has six, and fluorine has seven. complete the lewis structure for this covalent compound. f n = = = . : : 0 : reset next um. all rights reserved us 2