1
NDA 2017 Paper 1
MCQ (Single Correct Answer)
+2.5
-0.83
Which one of the following elements is used in pencil-lead?
A
Zinc
B
Lead
C
Carbon (Graphite)
D
Tin
2
NDA 2018 Paper 2
MCQ (Single Correct Answer)
+2.5
-0.83
The atomic number of an element is 8. How many electrons will it gain to form a compound with sodium?
A
One
B
Two
C
Three
D
Four
3
NDA 2018 Paper 2
MCQ (Single Correct Answer)
+2.5
-0.83
A sample of oxygen contains two isotopes of oxygen with masses 16u and 18u respectively. The proportion of these isotopes in the sample is 3 : 1. What will be the average atomic mass of oxygen in this sample?
A
17.5 u
B
17 u
C
16 u
D
16.5 u
4
NDA 2018 Paper 2
MCQ (Single Correct Answer)
+2.5
-0.83
Which one of the following is a heterogeneous mixture?
A
Hydrochloric acid
B
Vinegat
C
Milk
D
Soda Water
Questions Asked from Marks 2.5