A 0.338-gram sample of magnesium is completely reacted with oxygen to produce 0.560 g of magnesium oxide. What is the mass percentage of oxygen in magnesium oxide?

Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?

How would the number of moles (n) of o2 change if the atmospheric pressure doubled but all other variables stayed the same