Question

Calculate the number of protons, neutrons and electrons in .

Solution

Correct option is

35, 45, 35

 

Here, Z = 35, A = 80  

∴ No. of protons = Atomic No. = 35  

No. of neutrons = A – Z = 80 – 35 = 45.    

As the atom is neutral, No. of electrons = No. of protons = 35.

SIMILAR QUESTIONS

Q1

Calculate (a) wave number and (b) frequency of yellow radiations having wavelength of 5800 Å.

Q2

The Vividh Bharati station of All India Radio, Delhi broadcasts at a frequency of 1368kHz (kilohertz). Calculate the wavelength of the electromagnetic radiation emitted by the transmitter. Which part of the electromagnetic spectrum does it belong to? 

Q3

The wavelength range of the visible spectrum extends from violet (400 nm) to red (750 nm). Express these wavelengths in frequencies (Hz) (1 nm = 10–9 m) 

Q4

Calculate the frequency and energy of a photon of radiation having wavelength 6000 Å.

Q5

Calculate the energy of a mole of photons of radiations whose frequency is  ?

Q6

A 100 watt butt bulb emits monochromatic length of wavelength 400 nm. Calculate the number of photons emitted per second by the bulb.

Q7

Calculate the kinetic energy of the electron eject when yellow light of frequency 5.2 × 1014 sec–1 falls on the surface of potassium metal. Threshold frequency of potassium is 5 × 1014 sec–1.  

Q8

The threshold frequency v0 for a metal is 7.0 × 1014 s–1. Calculate the kinetic energy of an electron emitted when radiation of frequency v = 1.0 × 1015 s–1 hits this metal.