Exams

The four bonds of carbon tetrachloride (CCl4) are polar, but the molecule is nonpolar because the bond polarity is cancelled by the symmetric tetrahedral shape. Hence, making the net dipole as zero and molecule as non-polar.

When other atoms substitute for some of the Cl atoms, the symmetry is broken and the molecule becomes polar.

Dehydration is a loss of body fluid that impairs normal bodily functions. Serious dehydration may cause muscle cramps, reduced blood volume and increased heart rate.

River Congo is the only river which crosses the equator twice.

Joseph F. Glidden - Father of Barbed Wire.

• Glidden was born in New York in 1812. He invented Barbed Wire in 1873 and was granted the patent on Nov. 24, 1874. After a three year battle over the patent, which he eventually won received a patent for the modern invention in 1874 after he made his own modifications to previous versions.