Which would be an example of a homogeneous mixture? Question 10 options:

Sprite

marinara sauce

air

ranch dressing

Air

Explanation:

Air is an homogeneous mixture because it contain gaseous samples that have the same proportion throughout it's given sample. Air is a mixture of gaseous substances of 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, 1% of water vapor and small amounts of other gases in same proportion.

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.

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.