Category: Chemistry Basic Concept

A. sand
B. haemoglobin
C. diamond
D. maltose

A. 0.2m
B. 0.2mm
C. 0.2nm
D. 0.2pm

A. Relative abundance
B. Average mass of element
C. Number of isotopes
D. Relative isotopic mass

A. Pb3 O4
B. 2Pb CO3 – Pb (OH)2
C. Pb Cr O4 – Pb (OH)2
D. Pb2O

A. Electrons fill orbitals with parallel spins until all the orbitals of the same energy are half filled then they go into sub-shells with anti-parallel (opposite) spin.
B. The electrons in the same atom cannot have the same four quantum numbers
C. There is maximum of two electrons is an orbital.
D. None

A. 1-mole molecules of water
B. 1-gram molecule of water
C. 3-gram atoms
D. all