The water molecules are not completely removed so additional heating is required.
Explanation:
We have the copper (II) sulfate pentehydrate with the chemical formula CuSO₄ · 5H₂O.
molar mass of CuSO₄ · 5H₂O = 159.6 + 5 × 18 = 249.6 g/mole
Knowing this, we devise the following reasoning:
if in 249.6 g of CuSO₄ · 5H₂O there are 90 g of H₂O
then in 8 g of CuSO₄ · 5H₂O there are Y g of H₂O
Y = (8 × 90) / 249.6 = 2.88 g of water
mass of dried CuSO₄ = mass of CuSO₄ · 5H₂O - mass of H₂O
mass of dried CuSO₄ = 8 - 2.88 = 5.12 g
5.12 g is less that the weighted mass of 6.50 g. We deduce from this that the sample needs additional heating in order to remove all the water (H₂O) molecules.
Learn more about:
hydrates
brainly.com/question/10232217
brainly.com/question/13450632
#learnwithBrainly
Answer:
Highest speed: He
Lowest speed: CO2
Explanation:
The rms speed (average speed) of the molecules/atoms in an ideal gas is given by:

where
R is the gas constant
T is the absolute temperature of the gas
M is the molar mass of the gas, which is the mass of the gas per unit mole
From the equation, we see that at equal temperatures, the speed of the molecules in the gas is inversely proportional to the molar mass: the higher the molar mass, the lower the speed, and vice-versa.
In this problem, we have 5 gases:
(CO2) (O2) (He) (N2) (CH4)
Their molar mass is:
CO2: 44 g/mol
O2: 16 g/mol
He: 4 g/mol
N2: 14 g/mol
CH4: 16 g/mol
The gas with lowest molar mass is Helium (He): therefore, this is the gas with greatest average speed.
The gas with highest molar mass is CO2: therefore, this is the gas with lowest average speed.
Acting as a reference point for detecting motion
Answer:

Explanation:
Hello,
In this case, we apply the Gay-Lussac's law which allows us to understand the pressure-temperature behavior via a directly proportional relationship:

Thus, since we are asked to compute the final pressure we solve for it in the previous formula, considering the temperature in absolute Kelvin units:

Best regards.