I believe the answer would be A. Electronegativity increases across a period.
Answer:
helium hydrogen
Explanation:
lithium beryllium bottom carbon
Answer:
When heat is added to a substance, the molecules and atoms vibrate faster. As atoms vibrate faster, the space between atoms increases. The motion and spacing of the particles determines the state of matter of the substance. The end result of increased molecular motion is that the object expands and takes up more space.
hope this helps!!!!!!
Answer:
a mixture is a material made up of two or more different substances which are physically combined.
