Place the following in order of increasing f-a-f bond angle, where a represents the central atom in each molecule. a. pf3 < of2 < pf4 b. of2 < pf3 < pf4 c. of2 < pf4 < pf3 d. pf4 < of2 < pf3 e. pf4 < pf3 < of2 question # 7 place the following in order of increasing x-se-x bond angle

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

If 2 molecules of one reactant combine with 3 molecules of another to produce 5 molecules of a product, then what is the representation of the reaction?

El amoniaco y el fluor reaccionan para formar tetrafluoruro de dinitrogeno y fluoruro de hidrogeno. segun la reaccion: nh3 + f2 ⇒ n2f4 + hf si reaccionan 5 gramos de amoniaco y 20 gramos de fuor, ¿cuantos gramos de fluoruro de hidrogeno se producen?