Questions

The fireworks exhibition had awesome effects.

You have to consider three things.

1. First, are the bonds polar?

Look at differences in electronegativity and if  it is >0.5, bonds are polar.

2. Second, does the molecule have unshared electron pairs?

If so, they generally lead to a polar molecule.

3. Third, is the molecule symmetric?

If so, then although the bonds may be polar, the symmetry cancels out the individual bond polarity and the molecule is non polar.

CF4 follows all the rules above and has a symmetric distribution of charge, making it nonpolar. The others all have asymmetric charge distributions.

Hence, CF4 represents a Non-polar molecule.

Fuse Wire is Made of an alloy of Tin and Lead.

If too high a current flows, the element rises to a higher temperature and either directly melts, or else melts a soldered joint within the fuse, opening the circuit. Thefuse element is made of an alloy of Tin and Lead to provide stable and predictable characteristics.

In chemistry, Weak bonds are those forces of attraction that, do not take a large amount of energy to break.

For example, hydrogen bonds are broken by energies in the order of 4 - 5 kcal/mol.

Ionic bonds, hydrogen bonds and van der Waals interactions are considered weak bonds.

Weak bonds are transient and easily reversible.

India has been ranked 45th, down four notches from last year, in terms of competitiveness in the annual rankings compiled by IMD which saw Hong Kong topping the list. US was “pushed out” of the top three slots while Hong Kong consolidated its dominance of the annual rankings for the second year in the list compiled by the International Institute for Management Development’s (IMD) World Competitiveness Center.

Sukhna Lake is in Chandigarh, India.

It is a reservoir at the foothills of the Himalayas. It covers an area of 3 km². This rainfed lake was created in 1958 by damming the Sukhna Choe, a seasonal stream coming down from the Shivalik Hills.