Answer:
n = 3 for similar blue light
Explanation:
The principle applied here is energy levels and energy changes. There are different energy levels depending on the value of the integer as explained by Max planck - a german physicist in 1900, Max planck claimed that electrons in an atom were presumed to be oscillating with a frequency f, then there enrrgy will be given by the plancks equation ; E =hf, where h is the plancks constant.
In general energy of each level can be written as E =nhf
The mass of substance which consists the equal number of particles as 12 grams of Carbon-12 is said to be mole.
For example:
The balanced chemical equation for production of water from hydrogen and oxygen is:
That means 2 moles of reacts with 1 mole of
to give 2 moles of
.
The given formula is .
Hence, 4 represents the number of moles in formula that is 4 moles of
.
The number of atoms of sodium, in
is:
The number of atoms of sulfur, in
is:
The number of atoms of oxygen in, in
is:
Answer:
Mass, m = 19466.7 kg
Explanation:
Given that,
Portland cement concrete (PCC) has a density of 150 lb/ft³
We need to find how many kilograms of PCC are required to cast a cylindrical column 1.15 m in diameter and 7.8 m in height.
Since, 1 kg = 2.205 lb
1 lb/ft³ = 16.018 kg/m³
150 lb/ft³ = 2402.77 kg/m³
Density,
m is mass of PCC in kg and V is volume of cylinder
So, the mass of PCC required is 19466.7 kg.