Robert is testing two objects. Each object is composed of a single element unknown to Robert. Which of the following procedures could Robert SAFELY use to identify these elements. -He could measure the objects mass and volume in order to calculate each objects' density. Then, compare his densities to a elemental density chart.

-He could light each element on fire to see if they have flammability properties.

-He could drop each object off a building and see if they break, and or how they break.

-He could guess what element each object is made of.

Iknow #2 is d. i just need to know why

Elements that do not have full outer electron shells will donate, share, or take electrons from other atoms. choose the items that have the correct binary ionic formula.

Which is a difference between molecular compounds and ionic compounds? select the correct answer below: question 5 options: molecular compounds typically form between a metal and a nonmetal, while ionic compounds typically form between nonmetals. molecular compounds result from the transfer of electrons between atoms to form ions, while ionic compounds result from the sharing of electrons between neutral atoms. molecular compounds are formed of discrete, neutral molecules, while ionic compounds are formed of large repeating arrays of opposite charges. molecular compounds have high melting points and high boiling points, while ionic