1 mole of platinum has a mass of 195 g therefore 1 atom will have a mass of 195 g /(6.02 ×10^23) = 3.239 × 10^-22 g
Density is given by dividing mass by volume, thus to get volume, mass is divided by density.
The volume = (3.239 × 10^-22)/21.4
= 1.514 × 10^-23 cm³
But volume of a sphere is given by 4/3πr³
Therefore, r³ = 3.6129 × 10^-24
r = ∛(3.6129 × 10^-24)
= 1.534 × 10^ -8 cm
Therefore, the radius of the platinum atom is 1.534 × 10^-8 cm
Answer:
A. Clear and Sunny
Explanation:
The answer would be A. Clear and Sunny. A high pressure system occurs where the air mass above the Earth is denser than in surrounding areas, and therefore exerts a higher force or pressure. They usually happen with li9ght winds. Using process of elimination, it could not be D. Warm and Stormy, C. Cloudy and Rainy, or B. Cold and Stormy because all have wet climates.
Answer: 8moles
Explanation:
The reaction below shows the formation of 2 moles of water from 2 moles of hydrogen and 1 mole of oxygen respectively.
2H2(g) + O2 (g) --> 2H2O(l)
So, if 1 mole of O2 produce 2 mole of H2O
4 moles of O2 will produce Z mole of H2O
To get the value of Z, cross multiply
1 x Z = 4 x 2
Z = 8
So, the equation will be 8H2(g) + 4O2 (g) --> 8H2O(l)
Thus, 4 moles of O2 will produce 8moles of H2O .
In a car driven by a gasoline combustion engine, heat energy is quickly converted into kinetic energy which results in the motion of the car.
According to the law of the conservation of energy, energy cannot be destroyed or created. It is can only be transformed from one form to another.
Number of moles :
500 / 180.16 => 2.775 moles
Volume = 0.72 L
M = n / V
M = 2.775 / 0.72
M = 3.85 M
hope this helps!
