25.0(g) of pentane(C5H12) is combined with excess oxygen

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

An object resting on a table weighs 100 n. with what force is the object pushing on the table? with what force is the table pushing on the object? explain how you got your answer.

Use the de broglie's wave equation to find the wavelength of an electron moving at 4.5 × 106 m/s. show your work. note: h= plank's constant (6.62607 x 10-34 j s)