Answer:
400 mL
Explanation:
Given data:
Mass of barium = 2.17 g
Pressure = 748 mmHg (748/760 = 0.98 atm)
Temperature = 21 °C ( 273+ 21 = 294k)
Milliliters of H₂ evolved = ?
Solution:
chemical equation:
Ba + 2H₂O → Ba(OH)₂ + H₂
Number of moles of barium:
Number of moles = mass/ molar mass
Number of moles = 2.17 g / 137.327 g/mol
Number of moles = 0.016 mol
Now we will compare the moles of barium with H₂.
Ba : H₂
1 : 1
0.016 : 0.016
Milliliters of H₂:
PV = nRT
V = nRT/P
V = 0.016 mol × 0.0821 atm. mol⁻¹.k⁻¹.L×294 k/0.98 atm
V = 0.39 atm. L/0.98 atm
V = 0.4 L
L to mL
0.4 × 1000 = 400 mL
Answer:
are the best type of scientific investigation to demonstrate cause-and-effect relationships because they allow the investigator to actively manipulate variables and control conditions.
Answer:
Moles = Molecules / (6.0221415 x 10^23)
Explanation:
The molar mass of the protein is 45095 g/mol.
The mass of a sample of a chemical compound divided by the quantity, or number of moles in the sample, measured in moles, is known as the molar mass of that compound.
The expression of molar mass of protein is
M₂ = (W₂/P) (RT/V)
Given;
W₂ = 1.31g
P = 4.32 torr = 5.75 X 10⁻³ bar
R = 0.083 Lbar/mol/K
T = 25°C = 298.15 K
V = 125 ml = 0.125 L
Putting all the values in the above formula
M₂= (1.31 g/5.75 X 10⁻³ bar) X (0.083 Lbar/mol/K X 2)/0.125 L)
M₂ = 45095 g/mol
Thus, the molar mass of the protein is 45095 g/mol.
Learn more about the Molar mass with the help of the given link:
brainly.com/question/22997914
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The modern day model of an atom has a lot of questions answered about it answered and is very accurate while John's version was a very early model before technology was advanced enough to get more information on it so it was very basic and not as accurate as today's model. Hope this helps!