Which statement is true of a reversible reaction at equilibrium? the concentration of reactants is less than the concentration of products. the concentration of reactants and the concentration of products are equal. the concentration of reactants is greater than the concentration of products. the concentration of reactants and the concentration of products are constant. the concentration of reactants is decreasing and the concentration of products is increasing.

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.