Any substance changes to another substance that means the change of the physical property. Like water () has different state which changes as the temperature changes. It remain as liquid in the room temperature, in solid form at or below 0°C and vapor phase on or above 100°C. But in all the stage or phase of the substance the composition of the water i.e. remains. Thus the chemical property remains fixed when a substance change to other substance.
Steel is practically one of the worlds most important metals to use in construction, it is harder and stronger than iron can be. You can say iron is the base metal of steel, if you need more info, just ask :>
A MOLECULE IS MADE OF TWO OR MORE ELEMENTS CHEMICALLY COMBINED IS KNOWN AS A COMPUND.
A MOLECULE IS MADE OF TWO ATOMS IS JUST AN ELEMENT.
A MOLECULE MADE OF TWO OR MORE ELEMENTS IS KNOWN AS A COMPUND.
.......,ok first,WHAT THE WORLD THIS THAT!? And this may be how bread formed
Answer:
a) ammonium ion
b) amide ion
Explanation:
The order of decreasing bond angles of the three nitrogen species; ammonium ion, ammonia and amide ion is NH4+ >NH3> NH2-. Next we need to rationalize this order of decreasing bond angles from the valence shell electron pair repulsion (VSEPR) theory perspective.
First we must realize that all three nitrogen species contain a central sp3 hybridized carbon atom. This means that a tetrahedral geometry is ideally expected. Recall that the presence of lone pairs distorts molecular structures from the expected geometry based on VSEPR theory.
The amide ion contains two lone pairs of electrons. Remember that the presence of lone pairs causes greater repulsion than bond pairs on the outermost shell of the central atom. Hence, the amide ion has the least H-N-H bond angle of about 105°.
The ammonia molecule contains one lone pair, the repulsion caused by one lone pair is definitely bless than that caused by two lone pairs of electrons hence the bond angle of the H-N-H bond in ammonia is 107°.
The ammonium ion contains four bond pairs and no lone pair of electrons on the outermost nitrogen atom. Hence we expect a perfect tetrahedron with bond angle of 109°.
