Answer:
(a) Equation of reaction:
2Na + 2H20 = 2NaOH + H2
(b) 0.46g of sodium was used in the reaction
Explanation:
(a) 2 moles of sodium reacted with 2 moles of water to yield 2 moles of sodium hydroxide and 1 mole of hydrogen gas
(b) mass of hydrogen gas produced (m) = PVM/RT
P = 101.3kpa = 1atm, V = 246mL = 246cm^3, M = 2g/mol, R = 82.057cm^3.atm/gmol.K, T = 25°C = 25+273 = 298K
m = (1×246×2)/(82.057×298) = 0.02g of hydrogen gas
From the equation of reaction
2 moles (46g) of sodium produced 1 mole (2g) of hydrogen gas
0.02g of hydrogen gas was produced by (46×0.02)/2 = 0.46g of sodium
Answer:
94.1 %
Explanation:
We firstly determine the equation:
2H₂O + O₂ → 2H₂O₂
2 moles of water react to 1 mol of oxygen in order to produce 2 moles of oxygen peroxide.
We convert the mass of oxygen to moles:50 g . 1mol /32g = 1.56 mol
Certainly oxygen is the limiting reactant.
2 moles of water react to 1 mol of oxygen.
13 moles of water may react to 13/2 = 6.5 moles. (And we only have 1.56)
As we determine the limiting reactant we continue to the products:
1 mol of O₂ can produce 2 moles of H₂O₂
Then 1.56 moles of O₂ will produce (1.56 . 2) = 3.125 moles
We convert the moles to mass: 3.125 mol . 34 g/mol= 106.25 g
That's the 100% yield or it can be called theoretical yield.
Percent yield = (Yield produced / Theoretical yield) . 100
(100g / 106.25 g) . 100 = 94.1 %
A theory is something that has been proven a few times, so yes it’s been consistent in science but not enough. A law is something multiple scientists have proven to be true multiple times, causing it to be a law.
Answer:
Number of moles = No of mokecules/ Avigadro's number
Avigadro's number = 6.022*10(23)
No of moles = 1.505*10(24)/6.022*10(23)
No of moles =2.49 = 2.5mol
The number of mole is 2.5mol
Answer:
15.9gmol⁻¹
The gas could have been methane when we compare the two molecular masses.
Oxygen gas, O₂ also shares this same number for its molecular mass. This would be the reason why it would not be methane.
Explanation:
Given parameters:
Volume of gas at STP = 2.0L or 2.0dm³(1L = dm³)
Mass of the gas = 1.43g
Unknown:
Molecular mass of the gas = ?
Solution
We can find the number of moles using the mole concept according to the equation below:
number of moles = ³⁻¹
number of moles =
number of moles = 0.089mol
Using this obtained number of moles, we can derive the molecular mass of the compound by using the relationship between mass and number of moles according to the equation below:
molecular mass =
molecular mass =
molecular mass of the gas = 15.9gmol⁻¹
The formula of methane gas is CH₄.
Let's calculate the molecular mass of methane using these atomic masses:
C = 12g and H = 1g
The molecular mass = 12 + (1x4) = 16gmol⁻¹
The gas could have been methane when we compare the two molecular masses.
Oxygen gas, O₂ also shares this same number for its molecular mass. This would be the reason why it would not be methane.