Is boron an element a compound a heterogeneous mixture or a homogeneous mixture?

What happened in 2012 and how does it illustrate the importance of understanding the sun and how it works?

Particle model to predict what will happen if a sharp object creates a hole in the soccer ball

Identify one disadvantage to each of the following models of electron configuration: -dot structures -arrow and line diagrams -written electron configurations type in your answer below. (answer) -dot structures do not show the distribution of electrons in orbitals and take up a lot of space. -arrow and line diagrams take up a lot of space and make it difficult to count electrons. -written configurations make it easy to lose count of electrons and do not show the distribution of electrons in orbitals.