The number of electrons in the outermost shell and the number of neutrons in the nucleus of \(_{ 19 }X^{ 39 }\) are respectively
9,20
1,20
1,19
9,19
The total mass of the protons in an atom of an element is 16 u. Atomic number of the element is
less than 16
greater than 16
equal to 16
cannot be predicted
Identify the correct statement/so
\(\alpha \) - -particles when combine with two electrons yield Helium gas.
\(\beta \) -rays are negatively charged particles.
\(\gamma \) rays are high energy radiations like X-rays
All of the above
The number of protons, neutrons and electrons in \(_{ 35 }Br^{ 80 }\) are respectively
35,45,35
35,35,45
35,35,80
35,80,35
The radioactive isotope of hydrogen contains ________ no. of neutrons
0
1
2
3
The electronic configuration of an ion X-2 is 2,8,8 If its mass number is 32, the number of protons neutrons and electrons are respectively
18, 14, 18
16,16,16
14,18,24
None of these
Structures of nuclei of three atoms X, Y and Z are given below. X has 18 electrons and 22 neutrons Y has 20 protons and 20 neutrons Z has 19 protons and 20 neutrons Based on the above data which of the following statement is correct?
X and Yare isotopes, Y and Z are isobars
X and Yare isobars, Y and Z are isotopes
X and Y are isobars, Y and Z are isotones
None of the above
Which of the following will have equal number of electrons? (i)O-2 and F- (ii) Na+ and Mg2+ (iii) Ar and K+ (iv) Cl and Ar
i and ii
ii and iii
i, ii and iii
i,ii,iii and iv
Which of the following statement is incorrect about the model of atoms?
According to Rutherford's model electrons are moving around the nucleus with high velocity
Plum pudding model was proposed by J.J. Thomson
According to Bohr's model when an electron revolves in a particular orbit its energy does not change with time
Rutherford's model could explain the stability of the atom
Identify the wrong statement about cathode rays.
These consist of a stream of electrons
They are charged particles
Can be deflected by electric field
They have same velocity as that of light
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