Answer: a) 
b) 
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
a) Mass of Ba= 66.06 g
Mass of Cl = 34.0 g
Step 1 : convert given masses into moles.
Moles of Ba =
Moles of Cl = \frac{\text{ given mass of Cl}}{\text{ molar mass of Cl}}= \frac{34g}{35.5g/mole}=0.96moles[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For Ba = 
For O =
The ratio of Ba: Cl= 1:2
Hence the empirical formula is
b) Mass of Bi= 80.38 g
Mass of O= 18.46 g
Mass of H = 1.16 g
Step 1 : convert given masses into moles.
Moles of Bi =
Moles of O= 
Moles of H=
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For Bi= 
For O =
For H=
The ratio of Bi: O: H= 1:3: 3
Hence the empirical formula is
Answer:
0.125 mole
Explanation:
From Avogadro's hypothesis, we discovered that 1 mole of any substance contains 6.02x10^23 atoms.
The statement above suggests that 1 mole of chromium contains 6.02x10^23 atoms.
Now, if 1mole of of chromium contains 6.02x10^23 atoms,
Then Xmol of chromium contains 7.52x10^22 atoms i.e
Xmol of chromium = 7.52x10^22/6.02x10^23
Xmol of chromium = 0.125 mole
Therefore, 0.125 mole of chromium contains 7.52x10^22 atoms
It is less
effective to wash an insoluble precipitate with 15 ml of water once than it is
to wash the precipitate with 3 ml of water 5 times because commonly, when you
clean an <span>indissoluble
precipitate with water, the water will not be completely saturated with
contaminates. Therefore, the absorption of the contaminates would lower with
each wash, since if you only washed it once with a bigger amount or volume of
water, it’d become less contaminated with the wash water but it wouldn’t get
rinsed numerous times.</span>
Answer:
The final pressure is approximately 0.78 atm
Explanation:
The original temperature of the gas, T₁ = 263.0 K
The final temperature of the gas, T₂ = 298.0 K
The original volume of the gas, V₁ = 24.0 liters
The final volume of the gas, V₂ = 35.0 liters
The original pressure of the gas, P₁ = 1.00 atm
Let P₂ represent the final pressure, we get;
∴ The final pressure P₂ ≈ 0.78 atm.
1) Find the number of molecules in 7.88 g of sulfur
molar mass of S8 = 8*atomic mass of S = 8 * 32.0 g / mol = 256.0 g/mol
Number of moles = mass in grams / atomic mass = 7.88 g / 256.0 g / mol = 0.0308 moles
2) Find the mass of 0.0308 moles of P4
mass = number of moles * molar mass
molar mass of P4 = 4 * atomic mass of P = 4 * 31 g/mol = 124 g/mol
mass of P4 = 0.0308 moles * 124 g/mol = 3.8192g ≈ 3.82 g.
Answer: 3.82 grams of P4 will have the same number of molecules as 7.88 g of S8 (that is 0.0308 moles of molecules)
