2)As figuras a seguir constituem os sistemas fechados nós quais as bolinhas representam átomos. Classifique os sistemas I II III IV em substância composta ou mistura . I: II: III: IV: me ajuda prf​

Covalent network solids typically have melting points and boiling points. the chemical formula of a network solid indicates in the molecule.

Imagine that you’re getting ready to move to a new city. when people move, they are influenced by push factors and pull factors, and you have many reasons for your move. which of the following factors is an example of a pull factor? a. wanting to move because you’ve found a great new school somewhere new b. needing to move because there are not enough resources in your old hometown c. being forced to move because your old home is gone d. having to move because there are no jobs in your current hometown

The big bang nucleosynthesis theory states that elements were produced in the first few minutes of the big bang while elements have their origins in the interiors of stars, forming much later in the history of the universe.