Answer:
Explanation:
<u>1) Chemical equation (given)</u>
<u>2) Theoretical yield</u>
<u>a) Convert mass of NaHCO₃ to moles:</u>
- n = mass in grams / molar mass
- molar mass = 84.007 g/mol
- n = 2.36 g / 84.007 g/mol = 0.02809 mol
<u>b) Mole ratio:</u>
- 2 mol NaHCO₃ : 1 mol H₂CO₃
<u>c) Proportionality:</u>
- 2 mol NaHCO₃ / mol H₂CO₃ = 0.02809 mol NaHCO₃ / x
⇒ x = 0.2809 / 2 mol H₂CO₃ = 0.01405 mol H₂CO₃
<u>3) Actual yield</u>
<u>a) Mass balance</u>: 2.36 g - 1.57 g = 0.79 g
<u>b) Convert 0.79 g of carbonic acid to number of moles</u>:
- n = mass in grams / molar mass
- n = 0.79 g / 62.03 g/mol = 0.01274 mol
<u>4) Percentage yield, y (%)</u>
- y (%) = actual yield / theoretical yield × 100
- y (%) = 0.1274 mol / 0.1405 mol × 100 = 90.68%
The answer must show 3 significant figures, so y(%) = 90.7%.
Answer:
<em>It is known by almost everyone Earth is divided into longitudes and latitudes which are imaginary lines that cut Earth into 2 equal parts.</em>
Explanation:
The main use of dividing Earth into so many imaginary lines is to know no of places perfect location in numbers. Direction and tell tales can make the place talked about a bit confusing but the exact longitudes and latitudes known pill and someone in exact position.
So in the positions given the question 27 ° and 19 ° show the distance of longitude from Prime Meridian While 18 ° and two degrees show the distance from the equator.
Answer:
A = 8
B = 8
C = Oxygen (O)
D = 26
E = 30
F = Iron (Fe)
Explanation:
protons neutrons atomic number mass number element
A 7 B 15 C
D E 26 56 F
mass number = protons + neutrons
E = 56 - 26 = 30
A = 15 - 7 = 8
protons = atomic number
B = 8
D = 26
From atomic number:
C = Oxygen (O)
F = Iron (Fe)
The answer to your question is a