Why are moral or ethical questions NOT testable? A. They are questions that are impossible to answer. B. They are better answere
d by people who study history. C. The answers depend on people's opinions, not on observations. D. The answers are not something that would be asked about on a test.
Selenium falls in the same column with oxygen therefore it has the same number of valence electrons with oxygen which is 6. It fills the 3d orbital but only 4s and 4p are counted. The electronic configuration is [Ar]3d^10 4s^2.
Physical change is a temporary change. A chemical change is a permanent change.
Explanation:
A Physical change affects only physical properties i.e. shape, size, etc. Chemical change both physical and chemical properties of the substance including its composition.
