Answer:
16.8 L
Explanation:
From the question given above, the following data were obtained:
Number of mole of He = 0.750 mole
Volume of He =?
Recall:
1 mole of any gas occupy 22.4 L at STP. This also implies that 1 mole of He occupies 22.4 L at STP.
Finally, we shall determine the volume occupied by 0.750 mole of He. This can be obtained as follow:
1 mole of He occupied 22.4 L at STP.
Therefore, 0.750 mole of He will occupy = 0.750 × 22.4 = 16.8 L at STP.
Thus, 0.750 mole of He is equivalent to 16.8 L
Complete Question:
What volume of hydrogen will be produced at STP by the reaction 67.3 g of magnesium with excess water according to the following reaction?
Mg + 2H₂O --> Mg(OH)₂ + H₂
Answer:
62 L
Solution:
Step 1: Calculate Moles of Mg as;
Moles = Mass / M.Mass
Moles = 67.3 g / 24.30 g/mol
Moles = 2.76 moles of Mg
Step 2: <u>Calculate Moles of H₂ as;</u>
According to balance chemical equation,
1 mole of Mg produced = 1 mole of H₂
So,
2.76 moles of Mg will produce = X moles of H₂
Solving for X,
X = 2.76 mol × 1 mol / 1 mol
X = 2.76 mol
Step 3: <u>Calculating volume of H₂,</u>
1 mole of ideal H₂ occupies = 22.4 L Volume at STP
So,
2.76 moles of H₂ will occupy = X L of H₂ at STP
Solving for X,
X = 2.76 mol × 22.4 L / 1 mol
X = 61.82 L ≈ 62 L
Answer:
31.5mL
Explanation:
The following were obtained from the question:
C1 (concentration of stock solution) = 2M
V1 (volume of stock solution) =.?
C2 (concentration of diluted solution) = 0.630M
V2 (volume of diluted solution) = 100mL
Using the dilution formula C1V1 = C2V2, the volume of the stock solution needed can be obtained as follow:
C1V1 = C2V2
2 x V1 = 0.630 x 100
Divide both side by 2
V1 = (0.630 x 100) /2
V1 = 31.5mL
Therefore, 31.5mL of 2M solution of FeCl2 required
<u>Answer:</u> The average rate of disappearance of A is
<u>Explanation:</u>
The given chemical reaction follows:
The average rate of the reaction for disappearance of A is given as:
Or,
where,
= final concentration of A = 0.11 M
= initial concentration of A = 0.91 M
= final time = 90 minutes
= initial time = 0 minutes
Putting values in above equation, we get:
Hence, the average rate of disappearance of A is
Answer:
Explanation:
To convert from molecules to moles, we must use Avogadro's Number: 6.022*10²³. This tells us the amount of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are molecules of water.
Multiply by the given number of molecules.
Flip the fraction so the molecules of water cancel.
The original measurement of atoms has 2 significant figures ( 4 and 3), so our answer must have the same. For the moles we calculated, that is the tenth place. The 4 in the hundredth place tells us to leave the 1.
There are about 7.1 moles of water.