<u>Answer:</u> The wavelength of spectral line is 656 nm
<u>Explanation:</u>
To calculate the wavelength of light, we use Rydberg's Equation:
Where,
= Wavelength of radiation
= Rydberg's Constant = 
= Final energy level = 2
= Initial energy level = 3
Putting the values in above equation, we get:
Converting this into nanometers, we use the conversion factor:
So, 
Hence, the wavelength of spectral line is 656 nm
Answer:
Please see the attached pictures.
Explanation:
☆ To ensure that each carbon has 4 bonds, fill the other bonds with Hs.
Answer:
Mass of lava is 8370 g.
Explanation:
Density:
Density is equal to the mass of substance divided by its volume.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Given data:
density of lava = 3.1 g/cm³
volume= 2700 cm³
mass= ?
Solution:
d = m/v
m = d×v
m = 3.1 g/cm³×2700 cm³
m = 8370 g
All of them are properties of compounds except III.
for I, compounds are chemically combined together, so to separate them, we must use chemical methods like electrolysis or applying heat. These requires large amount of energy.
For II, they're always fixed. For example, in water (H2O), the ratio of hydrogen and oxygen is always 1:8 in mass. If there's some extra added, the substance becomes mixture instead of compounds.
For IV, after you chemically combined elements or compounds together, their properties are completely different. For example, iron can be attracted to magnets, but iron II sulphide does not.
Energy and the nature of the current
