1. a sample of argon at a pressure of 785 mm hg is transferred from a 125 ml dask to a 15 ml
assuming constant temperature, what is the pressure inside the 155 ml flask?

The pressure of argon inside the 155 ml flask is approximately 633 mm Hg.

Explanation:

Given:

The temperature is constant. So, the process is isothermal.

Initial pressure of argon is,

Initial volume of argon is,

Final volume of argon is,

Final pressure of argon is,

Now, as per Boyle's law, for an isothermal process, the product of pressure and volume is always a constant or . Therefore, we can write it as:

Rewriting the above in terms of , we have:

Plug in 785 for , 125 for , 155 for and solve for . This gives,

Therefore, the pressure of argon inside the 155 ml flask is approximately 633 mm Hg.

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%