Answer:
2.5litres
0.0005moles
0.56M
0.75M
0.1369M
0.255moles
0.0163M
0.10625M
3.312g
1221.14cm³
Explanations
1. 25÷1000=2.5l
2.Moles=Mass÷RFM
50÷1000÷(100)
0.0005moles
3.I litre=1000cm³
0.75litres=?
750cm³
0.42moles=750cm³
?=1000cm³
0.56M
4. Molarity=Conc. in g/l÷RFM
Conc.g/l
15g=500cm³
1000cm³
30g/l
Molarity
30÷(23+16+1)
0.75M
5.4.6g=250cm³
1000cm³
18.4g/l
Molarity
18.4÷(134.446)
0.1369M
6.3moles=1000cm³
(0.085×1000)
0.255moles
7.Conc.g/l
37.5cm³=0.181g
1000cm³
4.827g/l
Molarity=4.827÷(296)
0.0163M
Answer:
The number of formula units in 3.81 g of potassium chloride (KCl) is approximately 3.08 × 10²²
Explanation:
The given parameters is as follows;
The mass of potassium chloride produced in the chemical reaction (KCl) = 3.81 g
The required information = The number of formula units of potassium chloride (KCl)
The Molar Mass of KCl = 74.5513 g/mol
![The \ number \ of \ moles \ of \ a \ substance, n = \dfrac{The \ mass \ of \ the substance}{The \ Molar \ Mass \ of \ the \ substance}](https://tex.z-dn.net/?f=The%20%5C%20number%20%5C%20of%20%5C%20moles%20%5C%20of%20%5C%20a%20%5C%20substance%2C%20n%20%3D%20%5Cdfrac%7BThe%20%20%5C%20%20mass%20%20%5C%20%20of%20%20%5C%20%20the%20substance%7D%7BThe%20%20%20%5C%20%20Molar%20%20%5C%20%20%20Mass%20%20%20%5C%20%20of%20%20%5C%20%20%20the%20%20%20%5C%20%20substance%7D)
Therefore, we have;
![The \ number \ of \ moles \ of \ KCl= \dfrac{3.81 \ g}{74.5513 \ g/mol} \approx 0.051106 \ moles](https://tex.z-dn.net/?f=The%20%5C%20number%20%5C%20of%20%5C%20moles%20%5C%20of%20%5C%20KCl%3D%20%5Cdfrac%7B3.81%20%5C%20g%7D%7B74.5513%20%5C%20g%2Fmol%7D%20%5Capprox%200.051106%20%5C%20moles)
1 mole of a substance, contains Avogadro's number (6.022 × 10²³) of formula units
Therefore;
0.051106 moles of KCl contains 0.051106 × 6.022 × 10²³ ≈ 3.077588 × 10²² formula units
From which we have, the number of formula units in 3.81 g of potassium chloride (KCl) ≈ 3.08 × 10²² formula units.
I think this is done to allow even distribution of temperature in all the regions of the calorimeter. That is to make sure that there are no hot or cold spots and also ensure that the measured temperature is the actual average temperature when the readings are taken by a thermometer.
Answer:
80.7 L
Step-by-step explanation:
This looks like a case where we can use the Ideal Gas Law to calculate the volume.
pV = nRT Divide both sides by p
V = (nRT)/p
=====
Data:
n = 5.00 mol
R = 0.082 06 L·atm·K⁻¹mol⁻¹
T = (120 +273.15) K = 393.15K
p = 1520 mmHg × 1 atm/760 mmHg = 2.00 atm
=====
Calculation:
V = (5.00 × 0.082 06 × 393.15)/2.00
V = 161.3/2.00
V = 80.7 L
The formula for molarity is:
M = n/V
or
M = mol/L
All you need to do is substitute the values you are given.
M = 4.25
L = 2.5
n = ?
4.25 = n/2.5
Multiply both sides by 2.5 to isolate n.
10.625 = n
There are 10.6 moles of H2So4 in the aqueous solution.