The number of unpaired electrons in an atom of an element 8Q is _______?
2
4
6
8
Correct answer is A
No explanation has been provided for this answer.
The alkaline earth metals have similar chemical properties because________?
They are in the same period
Their salts are colourless
They have the same number of valence electrons
They are very reactive
Correct answer is C
No explanation has been provided for this answer.
Which of the following halogens is solid at room temperature?
Bromine
Chlorine
Flourine
Iodine
Correct answer is D
No explanation has been provided for this answer.
The gas given off when ethanol reacts with sodium is
Carbon(IV)oxide
Hydrogen
Methane
Oxygen
Correct answer is B
No explanation has been provided for this answer.
The following transition metal ions would be coloured in aqueous solution except________?
Cr3+
Fe3+
Mn3+
Sc3+
Correct answer is D
No explanation has been provided for this answer.