A0.55 g sample of h20 contains how many
molecules of water?
answer in units of molec.

Explanation:

Num of molecules = num of moles * Avogadro's constant (6.02* 10^23)

But num of moles = reacting mass / molar mass

Molar mass of H20= 2*1 + 16 = 2+16 = 18g

Reacting mass of H20 = 0.55g

Therefore, num of moles of H20 = 0.55g/18g = 0.031 moles

Therefore, num of molecules of H20 = 0.031 * 6.02*10^23

= 1.87*10^22 molecules of H20

calculate how many grams of ammonia can be produced from 4.21 grams of

n2 + 3h2 = 2nh3

my answer:

25.0g n2 x (1 mol/ 28.0gn2) x (2 mol nh3/ 1 mol n2) x (17.0g nh3/ 1 molnh3) = 30.36g n2

25.0g h2 x (1 mol h2/ 2.00g h2) x (2 mol nh3/ 3 mol h2) x (17.0g nh3/ 1 mol nh3) = 141.67g h2

lr = n2

< > according to newton's third law of motion, forces always act in equal but opposite pairs. another way of saying this is for every action, there is an equal but opposite reaction.< >