Answer:
The mass of an average copper atom is 
Explanation:
Given:
The total mass of copper atoms, 
Number of atoms, 
Now, we are asked to find the mass of 1 copper atom.
We use unitary method to find the mass of 1 copper atom.
Mass of 
atoms = m
∴ Mass of 1 atom = 
Plug in 63.5 for 'm', 
for 'N' and simply.
Mass of 1 atom = 
Therefore, the mass of an average copper atom is
The calculation for the amount of water present in the given amount of hydrate is shown below,
amount water = (100 g hydrate) x (0.347 g H2O / 0.946 g hydrate)
= 36.68 g
Thus, the amount of water present in the hydrate is approximately 36.68 g.
The moles of fluorine present are 71/19 = 3.74
Now, we know that one mole of gas at 273 K and 101.3 kPa (S.T.P.) occupies 22.4 liters
Volume of 3.74 moles at S.T.P = 3.74 x 22.4
Volume = 83.776 L = 83,776 mL
Now, we use Boyle's law, that for a given amount of gas,
PV = constant
P x 6843 = 101.3 x 83776
P = 1,240 kPa
Lets assume the gas is acting Ideally, then According to Ideal Gas Equation the density is given as,
d = P M / R T ------- (1)
Where;
P = Pressure = 1.03 atm
M = Molar Mass = 146.06 g/mol
R = Gas Constant = 0.08206 atm.L.mol⁻¹.K⁻¹
T = Temperature = 297 K
Putting Values in eq. 1,
d = (1.03 atm × 146.06 g/mol) ÷ (0.08206 atm.L.mol⁻¹.K⁻¹ × 297 K)
density = 6.17 g/L
Heat given out to the surroundings by the system = 225 J
Work done by the system on the surroundings = 645 J
According to the energy conservation, the energy can neither be created nor it can be destroyed, it can transform from one form to another. Hence, the energy which is lost to the surrounding as a work done and heat came from the internal energy of the system.
Hence, the change in the internal energy = - 225 - 645 = - 870 Joules
Negative sign means that the internal energy of the system is decreased by 870 Joules
