51. The particle with 13 protons and 10 electrons is

1. 1. AI - atom

   
   
   

   2. AI³⁺ ion

   
   
   

   3. nitrogen isotope

   
   
   

   4. none of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

---

52. Any P-orbital can accommodate up to

1. 1. 4-electrons

   
   
   

   2. 6-electrons

   
   
   

   3. 2-electrons in opposite

   
   
   

   4. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

---

---

53. The atoms of the elements having same mass number but different atomic number are called

1. 1. isotopes

   
   
   

   2. isobars

   
   
   

   3. isotones

   
   
   

   4. isomers

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

---

54. Bohr model can explain about

1. 1. Spectrum of Hydrogen atoms

   
   
   

   2. Spectrum of one atom/ion having one electron only

   
   
   

   3. Spectrum of Hydrogen molecule

   
   
   

   4. None of these

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

---

---

55. Regarding the atom of a chemical element, magnetic quantum number refers to

1. 1. orientation

   
   
   

   2. shape

   
   
   

   3. size

   
   
   

   4. spin

   
   
   

---

1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

---