When you burn paper you are chemically altering it so that is the correct answer. When you do all the other choices all of the components stay the same. Just because it changes shapes doesn't mean it'll change chemically toom
Answer:
trigonal pyramidal
Explanation:
In NF3, the nitrogen atom is sp3 hybridized. Now we must remember that according to the VSEPR theory, the number of electron pairs in the valence shell of the central atom in a molecule determines its shape.
Here, the nitrogen atom is the central atom and its outermost shell is surrounded by four electron pairs - one lone pair and three bond pairs. This means that it has a tetrahedral electron pair geometry.
However, due to the lone pair, the three fluorine atoms are arranged in a trigonal pyramidal geometry. Hence the correct shape of the molecule is trigonal pyramidal.
When solid <span>iron (iii) hydroxide is dissolved into water, it ionizes or it dissociates into ions. These ions are the iron (iii) ions and the hydroxide ions. Iron(III) oxide is classified as a base when in aqueous solution since it produces hydroxide ions. It is a weak base so it does not completely dissociate into the solution. The dissociation equation would be:
Fe(OH)3 <-----> Fe3+ + OH-
To write a complete reaction, the reaction should be balanced wherein the number of atoms of each element in the reactant side and the product side should be equal. Also, the phases of the substances should be written. We do as follows:
</span>
Fe(OH)3 (s) <-----> Fe3+ (aq) + 3OH- (aq)
<u>Answer:</u> The correct answer is Option A.
<u>Explanation:</u>
A catalyst is defined as the substance which increases the rate of the reaction without actually participating in the reaction.
This substance decreases the activation energy of the reactants, so as to proceed the reaction at a faster rate by increasing their effective collisions.
It does not affect the concentration of the reactants.
For the given reaction:

If we add NO, which is acting as a catalyst will increase the rate of the reaction to produce the products which is 
Hence, the correct answer is Option A.