Light travels at 299,792 kilometers per second making it the fastest thing out there but the question I have is how did light exist when there was only darkness
Answer:
[α] = -77.5° / 
Explanation:
Given;
Mass of optically pure substance in the solution = 10 g
Volume of water = 500 mL
Length of the polarimeter, l = 20 cm = 20 × 0.1 dm = 2 dm
measured rotation = - 3.10°
Now,
The specific rotation ( [α] ) is given as:
[α] = 
here,
α is the measured rotation = -3.10°
c is the concentration
or
c = 
or
c = 
or
c = 0.02 g/mL
on substituting the values, we get
[α] = 
or
[α] = -77.5° / 
2 mole Na needs 1 mole Cl2
4 mole Na = 2 mole Cl2
Answer:
2.3 x 10-23 g.
Explanation:
The mass of a single atom is the mass number, 14, is the mass in grams of one mole of carbon.
One mole of Nitrogen atom is 6.022 x 1023 atoms (Avogadro's number). This can then used to convert a nitogen atom to grams by the ratio:
mass of 1 atom / 1 atom = mass of a mole of atoms / 6.022 x 10^23 atoms.
mass of 1 atom = mass of a mole of atoms / 6.022 x 1023
mass of 1 N atom = 14 / 6.022 x 10^23 N atoms
mass of 1 N atom = 2.325 x 10^-23 g
The mass of a single Nitrogen atom is 2.325 x 10-23 g.