As we know that wavelength and frequency is inversely proportional to each other. Greater the wavelength smaller the frequency and vice versa.
Solution:
The relation between wavelength and frequency is as follow,
υ = c / λ
where
υ = frequency = ?
c = velocity of light = 3.0 × 10⁸ ms⁻¹
λ = wavenumber = 542 nm = 542 × 10⁻⁹ m
Putting the given values,
υ = 3.0 × 10⁸ ms⁻¹ / 542 × 10⁻⁹ m
Result:
υ = 5.53 × 10¹⁴ s⁻¹
Answer:
2. 14
Explanation:
To form Br₂ bond, a total of 14 electrons are needed.
Bromine is an element in the 7th group on the periodic table. It has 7 valence electrons.
- In forming the bromine gas, the two atoms of bromine shares 7 electrons each.
- These electrons are from their outermost shell.
- The outermost shell is the valence shell.
- So, two atoms donating 7 electrons gives 14 electrons.
B boiling point https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Map%3A_Introductory_Chemistry_(Tro)/03%3A_Matter_and_Energy/3.05%3A_Differences_in_Matter%3A_Physical_and_Chemical_Properties#Summary
The molar mass of CO2 is 44 grams per mole.
165 grams / 44 grams per mole of CO2 = 3.75 moles CO2
Using Avogadro’s law where 1 mole of substance equals
6.023 x 10^23 molecules
3.75 moles CO2 (6.023 x 10^23 molecules /mole) = 2.26 x 10^24 molecules CO2
