90 and 234 respectively
91 and 238 respectively
92 and 236 respectively
93 and 238 respectively
Correct answer is A
23892 X 234 90Y + 4 2 He Atomic number is 90 while mass number is 234
6.0
6.1
6.9
7.0
Correct answer is C
Contribution by isotope 6 = 6 x 1 = 6
contribution by isotope 7 = 7 x 12.5 = 87.5
This contribution is made by 1 + 12.5 = 13.5 atoms
Relative atomic mass of = 87.5 + 6 = 93.5/13.5 = 6.9
How many orbitals are in the d-sub shell?
1
3
5
7
Correct answer is C
No explanation has been provided for this answer.
In which of the following processes is biotechnology not applied?
Manufacture of drugs
Treatment of domestic sewage
Production of alcoholic beverages
Electroplating of metals
Correct answer is D
No explanation has been provided for this answer.
Which of the following substance is an alloy of lead?
Brass
Duralumin
Stainless steel
Soft solder
Correct answer is D
No explanation has been provided for this answer.