Valencia, who play Real Madrid next, had few problems against timid Athletic Bilbao.
Silva gave “Los Ches” the lead in the 35th minute after the Bilbao defence had failed to clear a corner.
The Spain striker then made it 2-0 on the hour with a classy goal, dancing around the defence and scoring with a left-foot blast.
Valencia are third with 59 points, 21 less than Real but seven ahead of fourth-placed Mallorca.
Bilbao, for their part, stay sixth, three points behind fifth- placed Sevilla.