HELP with Chemistry?

Question

(a) How many molecules of methane are found in 16.0g of methane gas?

(b) How many atoms of oxygen are found in one mole of oxygen gas?

(c) How many atoms of oxygen are found in one mole of ozone?

(d)How many moles of NaOH are found in 120g of NaOH?

(e) What is the mass, in grams, of 3.01x10^23 formula units of NaOH?

(f) What is the mass, in grams, of 6.023x^25 molecules of ethanol?

Show work plz.

(f) should be 6.023x10^25

Answer 1

A) 6.022x10^23 molecules since methane is approx 16.0 grams/mole.
(6.022x10^23 molecules/16.0 Periodic table Grams)X(16.0g from the problem/1)

B) 1.204x10^24 molecules since oxygen gas is O2 and it's asking for the moles of oxygen alone.
(6.022x10^23molecules O/1mole O)x(2 moles O/1 mole O2)x(1mole O2/1)

C) 1.806x10^24 molecules because ozone is O3
(6.022x10^23molecules O/1mole O)x(3 moles O/1 mole O3)x(1mole O3/1)

D) 2.4 moles because one mole of NaOH is approx 50g
(1moleNaOH / 50g NaOH) x (120g NaOH / 1)

E) 25g because 3.01x10^23 cules is half a mole and half a mole of NaOH is 25g.
(50g NaOH / 6.022x10^23 molecules) x (3.01x10^23 molecules / 1)

F) 4600g Ethanol. Ethanol is C2H6OH which is approx 46g.
(46g Ethanol / 6.022x10^23 molecules)x(6.023x10^25 molecules/1)
I hope that helps.

Answer 2

A) 16 g / mass of methane = moles methane

16 g / 16 g per mole (C = 12 , H = 1 x 4 )

B) oxygen gas = O2
1 mole = 6.02 x 10^23 atoms
2 O per mole, so 2 x 6.02 x 10^23 = atoms O2 in one mole O2

C) ozone = O3
3 x 6.02 x 10^23 = atoms O3 in one mole O3

D) 120 g / mass of NaOH
120 g / 40 grams per mole NaOH (Na = 23, O = 16, H = 1)

E) 3.01 x 10^25 / 6.02 x 10^23 = moles NaOH
moles NaOH x 40 g per mole (mass from above) = answer

F) 6.023 x 10^23 molecules ethanol / 6.02 x 10^23 = moles ethanol
moles ethanol x mass from periodic table = grams ethanol
C2H5OH mass (C = 12 x 2, H = 1 x 6, O = 16 x 1)

Answer 3

Atomic weights: Carbon = 12 H = 1 O = 16 Na = 23 CH4 = 16 O2 = 32 O3 = 48 NaOH = 40 C2H6O = 46

a. 6.023 x 10^23 because 16g = 1 mole

b. 1 molO2 x 2atomO/1molO2 x 6.023x10^23 = 12.046 x 10^23atomO = 1.2 x 10^24atomO

c. Ozone = O3, so 18.069 x 10^23 = 1.8 x 10^24

d. 120gNaOH x 1molNaOH/40gNaOH = 3molNaOH

e. 3.01x10^23fuNaOH x 1molNaOH/6.02x10^23fuNaOH x 40gNaOH/1molNaOH = 20gNaOH

f. 6.023x10^25molsEtOH x 1moleEtOH/6.023x10^23molsEtOH x 46gEtOH/1moleEtOH = 100/46 grams EtOH

10^25/10^23 = 100