Silicon melt at 1410 degree celsius. phosphonus melt at 44 degree celsius. Explain the difference in these melting point by referring to forces between the particles and energy.

An engineering team designs a new rocket that is faster and lighter than any other model being produced. however, the materials end up being so expensive that no company can afford to buy them. which step of the engineering process should have addressed this problem? a. know the background. b. evaluate the results. c. identify a need. d. do the work.

Can someone me with questions 15 to 17 plz.

If the density of water is 1.0 g/cm3, which of these materials would float in water, based on their densities? check all that apply. aluminum cork iron lead wax