Question

13. Contrast endothermic and exothermic reactions (Unit 1).

14. _______________ are the basic unit of matter. (Unit 1)
15. _________________ are pure substances made up of only one type of atom (i.e. hydrogen H) while __________________ are pure substances that are made up of two or more types of atoms in a specific ratio (i.e. carbon dioxide CO2). (Unit 1)
16. When a _______________ change occurs, the resulting substances have new/different properties. (Unit 1)
17. Contrast erosion and weathering. (Unit 2)

IF YOU DON'T HAVE THE ANSWER DON'T ANSWER also answer all if you can

Answer 1

13). Atoms are the basic unit of matter

14). Elements (pure substances, one type of atom) and Compound (made up of two or more types of atoms)

16). Chemical change

17). If a rock is changed or broken and stays where it is, it is weathering. If pieces of pebbles and soil from the rock are moved by natural forces, it is erosion

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