Langkow, the Coyotes' leading scorer, started the second-period deluge with a shorthanded tally at 6:25. He capped a three-minute outburst with his 27th to extend the Coyotes' advantage to 7-0.
Phoenix, which has just two wins in its last five games, was assured of a playoff spot with the victory coupled with Edmonton's 2-0 loss to Calgary. The Coyotes are tied with Los Angeles for the sixth seed in the Western Conference.
Robert Esche carried a shutout into the final period, but Pascal Dupuis scored his second goal in as many games with 10:29 remaining.