100 points! formation of an ion

aluminum is one of the most common elements in earth's crust, yet it is never found as a pure element in nature. that is, aluminum atoms are always combined with atoms of other elements, such as oxygen. an aluminum oxide compound you will recognize by its name is the gemstone called "ruby". its chemical formula is

al2o3

if every oxygen ion (combined with an aluminum ion) has a charge of -2, what must the charge of each aluminum ion be? how can you tell this? also, what has to happen to an uncharged aluminum atom so that it will bond with oxygen?

disclaimer: if the question is not answered fully or if it makes no sense it will be reported

How does a scientist the government? a. the scientist tells people in society what to do. b. the scientist determines the policies that the government spends money on. c. the scientist provides unbiased information to the government. d. the scientist makes laws based on his or her research results.

A50.0g sample of liquid water at 0.0 c ends up as ice at -20.0 c. how much energy is involved in this change?

Imagine that a new planet is discovered with two moons of equal mass: moon a and moon b. the mass of the new planet is greater than the combined mass of its moons. moon a is farther away from the new planet than moon b. what is the planet's gravitational pull on moon a compared to the planet's gravitational pull on moon b? the planet's gravity repels moon a with a greater force than it repels moon b, which is why moon a is farther away. the gravitational pull on moon b is greater than on moon a because moon b is closer to the new planet than moon a. the gravitational pull on moon b is greater than on moon a because moon b is farther away from the new planet than moon a. the gravitational pull on moon a is the same as the gravitational pull on moon b because distance does not affect the planet's gravity.