True
The main chemicals in air pollution that create acid rain are sulfur dioxide (SO2) and nitrogen (NOx).
Answer:
<em>The three gases, in the three identical containers, will all have the same number of molecules</em>
Explanation:
If these three gases (Helium He, Neon Ne, and Oxygen 
) are all contained in separate identical containers with the same volume. And they are all stored at the same temperature, and pressure. Then, they'll all contain the same number of molecules. This is in line with Avogadro's law which states that "Equal volume of all gases, at the same temperature and pressure, have the same number of molecules."
Answer:
2.04 x 10²⁴ molecules
Explanation:
Given parameters:
Mass of Be(OH)₂ = 145.5g
To calculate the number of molecules in this mass of Be(OH)₂ we follow the following steps:
>> Calculate the number of moles first using the formula below:
Number of moles = mass/molarmass
Since we have been given the mass, let us derive the molar mass of Be(OH)₂
Atomic mass of Be = 9g
O = 16g
H = 1g
Molar Mass = 9 + 2(16 + 1)
= 9 + 34
= 43g/mol
Number of moles = 145.5/43 = 3.38mol
>>> We know that a mole is the amount of substance that contains Avogadro’s number of particles. The particles can be atoms, molecules, particles etc. Therefore we use the expression below to determine the number of molecules in 3.38mol of Be(OH)₂:
Number of
molecules= number of moles x 6.02 x 10²³
Number of molecules= 3.38 x 6.02 x 10²³
= 20.37 x 10²³ molecules
= 2.04 x 10²⁴ molecules
