Compounds are made up of different kinds of atoms that are chemically combined. What do compounds have in common? A. They have the same color. B. They have the same melting point. C. They can be broken down into simpler substances. D. They cannot combine with one another to form more complex substances.

D

Explanation:

They cannot combine with one another to form more complex substances. that's the answer

chemical properties are the characteristic of matter which can only be observed by changing the chemical identity of a sample like flammability reactivity and toxicity.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.