SAT - Science - Chemistry - Atomic Structure

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Question - 1

The number of electrons in the outermost shell and the number of neutrons in the nucleus of \(_{ 19 }X^{ 39 }\) are respectively

  • A 9,20
  • B 1,20
  • C 1,19
  • D 9,19

Question - 2

The total mass of the protons in an atom of an element is 16 u. Atomic number of the element is

  • A less than 16
  • B greater than 16
  • C equal to 16
  • D cannot be predicted

Question - 3

Identify the correct statement/so

  • A \(\alpha \) - -particles when combine with two electrons yield Helium gas.
  • B \(\beta \) -rays are negatively charged particles. 
  • C \(\gamma \) rays are high energy radiations like X-rays 
  • D All of the above

Question - 4

The number of protons, neutrons and electrons in \(_{ 35 }Br^{ 80 }\) are respectively

  • A 35,45,35
  • B 35,35,45
  • C 35,35,80
  • D 35,80,35

Question - 5

The radioactive isotope of hydrogen contains ________ no. of neutrons

  • A 0
  • B 1
  • C 2
  • D 3

Question - 6

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

  • A 18, 14, 18
  • B 16,16,16
  • C 14,18,24
  • D None of these

Question - 7

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?

  • A X and Yare isotopes, Y and Z are isobars
  • B X and Yare isobars, Y and Z are isotopes
  • C X and Y are isobars, Y and Z are isotones
  • D None of the above

Question - 8

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

  • A i and ii
  • B ii and iii
  • C i, ii and iii
  • D i,ii,iii and iv

Question - 9

Which of the following statement is incorrect about the model of atoms? 

  • A According to Rutherford's model electrons are moving around the nucleus with high velocity
  • B Plum pudding model was proposed by J.J. Thomson
  • C According to Bohr's model when an electron revolves in a particular orbit its energy does not change with time
  • D Rutherford's model could explain the stability of the atom

Question - 10

Identify the wrong statement about cathode rays.

  • A These consist of a stream of electrons
  • B They are charged particles
  • C Can be deflected by electric field
  • D They have same velocity as that of light
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