Explanation:
Molar mass of Hg = 200.59g/mol.
Therefore Moles = Mass / Molar mass
= 100g / (200.59g/mol) = 0.499mol.
MCu: 63,5 g/mol
4 × mCu = 63,5×4 = 254 g
254g ------ 0,39%
Xg ---------- 100%
X = (254×100)/0,39
X = 65128,2 g/ mol <<<< molar mass
Answer:
The mole fraction of N₂ is 0.26.
Explanation:
The pressure exerted by a particular gas in a mixture is known as its partial pressure. So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:
PT = PA + PB
This relationship is due to the assumption that there are no attractive forces between the gases.
Dalton's partial pressure law can also be expressed in terms of the mole fraction of the gas in the mixture. The mole fraction is a dimensionless quantity that expresses the ratio of the number of moles of a component to the number of moles of all the components present.
So in a mixture of two or more gases, the partial pressure of gas A can be expressed as:
PA = XA * PT
In this case:
- PA= PN₂= 300 torr
- XA=XN₂= ?
- PT= 1.50 atm= 1140 torr (being 1 atm= 760 torr)
Replacing:
300 torr= XN₂*1140 torr
Solving:

XN₂= 0.26
<u><em>The mole fraction of N₂ is 0.26.</em></u>
Answer:
8.61 mL of the HCl solution
Explanation:
The reaction that takes place is:
- 2HCl + Mg(OH)₂ → MgCl₂ + 2H₂O
From the given mass of Mg(OH)₂, we can calculate <u>the moles of HCl that are neutralized</u>:
- 4x10² mg = 400 mg = 0.400g
- 0.400g Mg(OH)₂ ÷ 58.32g/1mol = 6.859*10⁻³ mol Mg(OH)₂
- 6.859*10⁻³ mol Mg(OH)₂ *
3.429x10⁻³ mol HCl
Finally, to calculate the volume of an HCl solution, we need both the moles and the concentration. We can <u>calculate the concentration using the pH value</u>:
= [H⁺]
- 0.0398 M = [H⁺] = [HCl] *Because HCl is a strong acid*
Thus, the volume is:
- 0.0398 M = 3.429x10⁻³mol HCl / Volume
- Volume = 8.616x10⁻³ L = 8.62 mL
Answer:
Explanation:
A measurement is the action of measuring something, or some amount of stuff. So it is important to measure certain things right, distance, time, and accuracy are all great things to measure. By measuring these things or in other words, by taking these measurements we can better understand the world around us.