Nation Grooming Institute of Science

06/12/2014

06/12/2014

Samples of 1 Mol of Some Common Substances.

29/11/2014

A trickle of liquid oxygen is deflected by a magnetic field, illustrating its paramagnetic property

27/11/2014

type of changes in chemistry

20/11/2014

Oxidation-reduction reactions (redox reactions) are reactions in which electrons are lost by an atom or ion in one reactant and gained by an atom or ion in another reactant. Although electrons are gained and lost in these reactions, the balanced equation for a redox reaction does not show the electrons that are being transferred. In order to tell whether a redox reaction has occurred or not, we need a way to keep track of electrons. The best way to do so is by assigning oxidation numbers to the atoms or ions involved in a chemical reaction.

19/11/2014

Density at different temperatures

Water at:

30°C is 0.9957 g cm-³
4°C is 1.0000 g cm-³
0°C is 0.9998 g cm-³

19/11/2014

Why does ice float in water?

Each water molecule is made up of two hydrogen (H) atoms and one oxygen (O) atom. The bonds between water molecules are called hydrogen bonds.
As water cools to 3.98°C, its mass stays the same but volume decreases – the same mass fits into a smaller space so it is more compact.
When water freezes at 0°C, the mass stays the same but its volume expands by 9 percent.
In liquid water, molecules are attracted to each other and temporarily held together by hydrogen bonds.
When water freezes at 0°C, a rigid open lattice (like a web) of hydrogen-bonded molecules is formed. It is this open structure that makes ice less dense than liquid water. This is why icebergs float.

19/11/2014

Water density changes with temperature and salinity. Density is measured as mass (g) per unit of volume (cm³). Water is densest at 3.98°C and is least dense at 0°C (freezing point).

18/11/2014

Is there any difference between Mass and Weight ?

Well, mass is a measurement of how much matter is in an object; weight is a measurement of how hard gravity is pulling on that object. Your mass is the same wherever you are--on Earth, on the moon, floating in space--because the amount of stuff you're made of doesn't change. But your weight depends on how much gravity is acting on you at the moment;

18/11/2014

Hereby,i would like to share some basic Knowledge of Science that may help you in your life, !!!!