The gas flows from higher concentration/pressure to lower concentration/pressure, which is outside the ball.
Answer:
En el caso del sodio, la valencia es 1, ya que tiene un solo electrón de valencia, si pierde un electrón se queda con el último nivel completo.
Explanation:
Grupo de la tabla periódica Electrones de valencia
Grupo 14 (IV) (Grupo del carbono) 4
Grupo 15 (V) (Grupo del nitrógeno ) 5
They all have the same number of electrons in the electron cloud.
The answer should be B, it reacts in air to form a green layer.
Chemical properties means that how the substance that reacts with other substance to produce new substances. Usually it cannot be measured or observed just with the substance itself.
From all the options above, only B is a reaction. The green layer formed is a new substance produced by copper and air. It involves a chemical change.
Other options like boiling points or state of matter, these are physical properties. They do not require it to react to other substances and the can be measured and observed easily.