ASAP Why do elements within a period of the periodic table have different
properties?
A. They have different arrangements of core electrons.
B. They have different numbers of valence electrons.
C. Some are metals and some are nonmetals.
D. They have different combinations of protons and neutrons.

Which is a characteristic of mixtures?

Consider the following reaction at equilibrium. 2co2 (g) 2co (g) + o2 (g) h° = -514 kj le châtelier's principle predicts that the equilibrium partial pressure of co (g) can be maximized by carrying out the reaction a. at high temperature and high pressure b. at high temperature and low pressure c. at low temperature and low pressure d. at low temperature and high pressure e. in the presence of solid carbon

Which of these statements best explains why space exploration should be encouraged? it prepares humans to live without oxygen. it dispel myths about objects in space. it prevents comets and asteroids from striking earth. it creates technology to absorb harmful radiations in space.