Yes it is a pure substance
N=3^K-1 I really don't know how to explain it but that's the formula <span />
Answer:
The non-metals or non-metallic elements; hydrogen (H), carbon (C), nitrogen (N), oxygen (O), phosphorus (P), sulphur (sulfer) (S), selenium (Se), (Uuo may belong here) and the noble gases form a relatively small group with a step like pattern towards the left-hand side of the periodic table (hydrogen being the odd one .
<u>Answer:</u> The correct options are A and E
<u>Explanation:</u>
A chemical reaction is defined as the reaction in which two or more chemical substances react to form two or more different chemical substances.
A new substance (product) is formed in a chemical reaction when the bonds between the reactants are broken so that the new bonds between the products can be formed.
For a given chemical reaction:

Here,
HF is a covalent compound as sharing of electrons take place between hydrogen and fluorine atom
NaOH is an ionic compound as a complete transfer of electrons occurs from sodium to hydroxide.
Thus, to form the products, an ionic bond between sodium and hydroxide must be broken coupled with a covalent bond between hydrogen and fluorine.
Hence, the correct options are A and E
Answer:
Explanation:
Nucleons include protons and neutrons. All the positive charge of an atom is contained in the nucleus, and originates from the protons. Neutrons are neutrally-charged. Electrons, which are negatively-charged, are located outside of the nucleus.