Atomic Mass and Composition of Nucleus

Isotope are species of atoms of a chemical element with the same atomic number and nearly identical chemical behaviour but with different atomic masses and physical properties.

$1 \mathrm{u}=$_____$\times {10}^{-27 }\mathrm{kg}$

The unified atomic mass unit, which is depicted by u, is equal to the ${\frac{1}{12}}^{\mathrm{th}}$ of the mass of an atom of _____-$12$ isotope.

Isobars are atoms (nuclides) having same atomic mass number but the different atomic number.

Isotopes that emits radiation are called _____. (radioisotope / stable isotope)

Assertion : $\mathrm{C}$ and $\mathrm{Si}$ both have same lattice structure, having $4$ bonding electrons in each. However, $\mathrm{C}$ is insulator where as $\mathrm{Si}$ is intrinsic semiconductor.
Reason : The four bonding electrons in the case of $\mathrm{C}$ lie in the second orbit, whereas in the case of $\mathrm{Si}$ they lie in the third.

Which of the following gives the correct number of protons and neutrons in a nucleus of carbon-$14 \left({}_6{}^{14}C\right)?$

The mass number of an atom $A=38$ and its electronic configuration is $1s^2 2 s^2 2p^6 3s^2 3p^4$. The number of neutrons and protons in the nucleus will be

${}_{10}{}^{22}\mathrm{Ne}$ nucleus, after absorbing energy, decays into two $\alpha$-particles and an unknown nucleus. The name of unknown nucleus is _____.

When atoms are bombarded with the alpha particles, only a few in a million suffer deflection and the others pass out undeflected. This is because

Rutherford's experiment on scattering of particles showed that an atom has

Nucleus of an atom consists of protons and electrons.

In the decay process, select the incorrect statement $A\stackrel{-\alpha }{\to }B\stackrel{-\beta }{\to }C\stackrel{-\beta }{\to }D$

The number of radioactive isotope of Hydrogen and total number of isotopes of Hydrogen are:

The proton and neutron are collectively called as

The nucleus of helium contains

............... has a pair of isomers

Complete the following nuclear reaction:

${}_{4}B{e}^9+{}_{2}H{e}^4\to {}_6{C}^{12}+\dots$

The nucleus consists of

Which of the following statements about the mass of an atom is true ?