Target: 10 Questions in 10 minutes

An IB Chemistry data booklet is helpful
1. Which of the following statements is FALSE?
  • A. The nucleus of an atom contains protons and neutrons
  • B. Negatively charged electrons occupy the space outside the nucleus
  • C. Atoms contain a positively charged dense nucleus
  • D. The number of electrons in an atom equals the number of neutrons

2. What is the atomic number of an atom which has 30 electrons and 35 neutrons?

  • A.   30
  • B.   35
  • C.   65
  • D.   105

3. How many protons, neutrons and electrons are present in each atom of 39K?

  Protons Neutrons Electrons
A 19 20 19
B 19 39 19
C 20 39 20
D 20 19 20

4. What is the correct symbol for the species which contains 13 protons, 14 neutrons and 10 electrons?

  • A.  
27 Si3+
14
 
  • B.  
 27 Si
14
 
  • C.  
 27 Al3+
13
 
  • D.  
 24 Al+
13

5. Which of the following species are isoelectronic (contain the same number of electrons)?

    I.   16 O2-    
 8
 
    II.   24 Mg2+    
12
 
    III.  29 Si    
14
  • A.   I and II only
  • B.   I and III only
  • C.   II and III only
  • D.   I, II and III
6. Which statement about two isotopes of an element is TRUE?
  • A.   They have the same number of neutrons
  • B.   They have different numbers of electrons
  • C.   They have the same chemical properties
  • D.   The have different atomic numbers

7. Which of the species below have the smallest number of neutrons?

  • A.  
198 Pt
78
 
  • B.  
 197 Au
79
 
  • C.  
 205 Ti
81
 
  • D.  
 204 Po
84

8. A sample of an unknown element “Z” consists of 3 isotopes as shown below:

Isotope Percentage Abundance /%
64Z 89.43
65Z 7.15
66Z 3.42
 

What is the relative atomic mass of element “Z” to 2dp?

  • A.   64.11
  • B.   64.12
  • C.   64.13
  • D.   64.14

9. The relative atomic mass of Indium is 114.816. Indium consists of two isotopes, 113In and 115In. What is the percentage abundance of the isotope 113In?

  • A.   8.8%
  • B.   9.0%
  • C.   9.2%
  • D.   9.4%

10. What is the relative atomic mass of zirconium from the information shown in the table below?

Isotope Percentage Abundance /%
90Zr 51.5
91Zr 11.2
92Zr 17.1
94Zr 17.4
96Zr 2.8
 
  • A.   90.9
  • B.   91.3
  • C.   91.7
  • D.   92.1