Answer: 0.37g
Explanation:avogadro number = 6.02214076x10^23 atoms/molecules per mole
a mole of Na2O = 2*23 + 16 = 52 g
4.25x10^21 atoms = 52*(4.25*10^21/6.02214076*10^23) = 0.37 g
Answer:
The percent yield of NaCl is 78.7 %
Explanation:
CuCl₂ + 2NaNO₃ → Cu(NO₃)₂ + 2NaCl
If the NaNO₃ is determined to be in excess, the limiting reagent is the chloride. We convert the mass to moles:
31 g . 1mol / 134.45g = 0.230 moles
Ratio is 1:2, so we can make a rule of three to determine the theoretical yield
1 mol of copper (II) chloride reacts to produce 2 moles of sodium chloride
Then, 0.230 moles of CuCl₂ will react to produce (0.230 .2) /1 ) = 0.461 moles of NaCl → we convert the moles to mass → 0.461 mol . 58.45 g / 1mol = 26.9 g
To find percent yield we do → (Yield produced / Theoretical yield) . 100
(21.2 g / 26.9 g) . 100 = 78.7 %
You correctly said that you need the combined gas law.
combine gas law----> P1V1/T1= P2V2/T2
P1= ?
V1= 2.58 L
T1= 368K
P2= 777 torr
V2= 1.53 L
T2= 495K
Now we plug in the values.
(P1 X 2.58)/ 368= (777 X 1.53)/ 495 K
P1= 343 torr
4.0 mol. 6.02 x 10. 23 atoms. 3. How many moles are in 2.5g of lithium? 2.5 grams Li. 1 mole. = 0.36 mol. 6.9 g. 4. Find the mass of 4.8moles of iron. 4.8 moles.
Answer:
c. 39
Explanation:
You round the number 39.098 to make it easier. Since you can't round it up to forty because the number after the 9 in-front of the decimal is a over i is unable to be rounded up