Peroxyacetyl nitrate PAN là chất gây kích ứng phổi có trong khói quang hóa. Giả sử sự phân hủy của PAN tuân theo động học bậc 1, có hằng số tốc độ 0,0217 s-1
. Xác định thời gian để ½ lượng PAN biến mất.

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

Ageochemist examines a piece of metal that he found in the soil. he performs tests to identify the metal from its density, electrical conductivity, and melting point. which statement best describes his investigation? a. he is determining physical properties that are sufficient to identify the metal.b. he is determining chemical properties that are sufficient to identify the metal.c. he is determining physical properties that are insufficient to identify the metal.d. he is determining chemical properties that are insufficient to identify the metal.

Ajet plane is speeding down the runway during takeoff. air resistance is not negligible. identify the forces on the jet.