Question 13 (2 points) Which statement best describes energy in an open system? (2 points)
All energy and matter are contained within the system,
b
Energy and matter flow into and out of the system,
Оe
Matter flows into and out of the system; energy does not
Od
There is no energy in an open system, there is matter

100 points answer quick the table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 10 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.

The volume of helium in a blimp is 6.28 x 10^9 millimeters. the density of helium in the blimp is .1786 kilogram/meter^3. find the mass of the helium in the blimp.

What material does not melt at any temperature