Calculate the wavelength of an electron (m = 9.11 x 10-28 g) moving at 3.66 x 100 m/s. a) 1.81 x 10-10 m b) 2.76 x 10-9 m c) 5.03 x 10-10 m d) 5.52 x 10-9 m e) 1.99 x 10-10 m

option e = 1.99 × 10⁻⁶ m

Explanation:

Given data:

Mass of electron = 9.11 × 10⁻²⁸ g   or 9.11 × 10⁻³¹ Kg

Velocity = 3.66 × 100 m/s

Wavelength = ?

Solution:

Formula:

λ  = h / m. v

λ  = wavelength

h = planck's constant

m = mass

v = velocity

Now we will put the values in equation

λ  = h / m. v

λ  =  6.63 × 10⁻³⁴ Kg. m²/s  / 3.66 × 100 m/s . 9.11 × 10⁻³¹ Kg

λ  =  6.63 × 10⁻³⁴ Kg. m²/s / 3334.26  × 10⁻³¹ Kg .m/s

λ  = 1.99 × 10⁻⁶ m

E) 1.99 x 10^-10 m

We are given;

The mass of an electron (m)as 9.11 x 10^-28 g

Speed of the electron (v) is 3.66 x 10^6 m/s.

We are required to find the wavelength of the electron.

This can be done using the  De Broglies wavelength Formula:

λ = h/mv; where λ is the electron wavelength, v is the speed of the electron, m is the mass of the electron and h is the plank's constant (6.626×10^-34)

Therefore;

Wavelength = (6.626×10^-34)÷(9.11 x 10^-28 g × 3.66 x 10^6 m/s)

                    = 1.987 ×10^-10 m

                    = 1.99 × 10^-10 m

Therefore, the wavelength of an electron is 1.99 × 10^-10 m

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.