Which of the following ions has an electron configuration different from the other?
17CI-
8O2-
12Mg2+
13AI3+
Correct answer is A
\(_{17}\)Cl\(^-\) = 18 electrons = 2, 8, 8
\(_{12}\)Mg\(^{2+}\), \(_{8}\)O\(^{2-}\) and \(_{13}\)Al\(^{3+}\) all have 10 electrons = 2, 8.
Which of the following electron configurations represents that of an atom in its ground state?
1s 22s12p1
1s22s22p63s13p1
1s22s12p3
1s22s22p63s0
Correct answer is D
The ground state of an electron, the energy level it normally occupies, is the state of lowest energy for that electron.
The number of orbitals in a p-sub level of an atom is
2
3
5
6
Correct answer is B
The p- orbital has 3 subshells; P\(_x\), P\(_y\) and P\(_z\) subshells.
Which of the following statements about thermoplastic material is correct? They
do not melt on heating
harden on heating
decompose on heating
soften and melt on heating
Correct answer is D
No explanation has been provided for this answer.
Cu and Mg
Cu and Sn
Cu and Zn
Cu and Pb
Correct answer is B
Bronze is an alloy consisting primarily of copper, tin and often with the addition of other metals (such as aluminium, manganese, nickel or zinc) and sometimes non-metals or metalloids such as arsenic, phosphorus or silicon.