Why do group 16 elements have a -2 charge

Express the following number in scientific notation. 0.026890 =

In which environment would primary succession occur? a forest with a few remaining trees after a recent wildfire an area of exposed rock after a glacier melts away beach that is exposed to the air at low tide an abandoned baseball field in a small town

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.