Answer: Air
Explanation: Pure air is a mixture of several gases that are invisible and odorless. Consists of 78% nitrogen, 21% oxygen, and less than 1% of argon, carbon dioxide.

<h3><u>Basic </u><u>Characteristic </u><u>of </u><u>acids </u></h3>
- Acids are sour in taste
- Acid turns blue litmus paper or solution into red litmus paper or solution
- Acids are good conductor of electricity because it dissociate into cation in aqueous solution
- Acids classified into edible acids and non edible acids. Non edible acids are very hazardous
- Generally, All acids are soluble in water
- Acids have PH smaller than 7
<u>Arrhenius </u><u>definition </u><u>of </u><u>acids </u><u>:</u><u>-</u>
According to Arrehinus,
- Acids are those substances which when dissolve in water given H positive ions . Then, this hydrogen ions combine with water to form H30 + ions
<u>Second </u><u>definition </u><u>of </u><u>Acids </u><u>was </u><u>given </u><u>by </u><u>Bonsted </u><u>Lowry </u><u>:</u><u>-</u>
According to Bonsted Lowry
- Acids are the proton donors that is when acids dissociate into water gives hydrogen ions that is H+ ions
<u>3rd </u><u>definition </u><u>was </u><u>given </u><u>by </u><u>Lewis </u>
According to Lewis
- Acids are those substances which have the ability to accept a pair of electrons .
Example of Acids
- HNO3 :- Nitric acid
- H2SO4 :- Sulfuric acid
- HCl :- Hydrochloric acid
<h3><u>Basic </u><u>characterists </u><u>of </u><u>bases </u></h3>
- Bases are bitter in taste
- Bases turns red litmus paper into blue litmus paper or solution
- Bases are also good conductor of electricity because on dissociation it produces anion in aqueous solution
- Bases are also good conductor of electricity
- When bases are soluble in water then they are known as alkaline base
- Bases have PH greater than 7
<u>Arrehinus definition of bases :-</u>
According to Arrehinus ,
- Bases are those substances which when dissolve in water produce OH negative ions that is hydroxide ions
<u>Bonsted Lowry definition </u>
According to Bonsted Lowry
- Bases are the proton donors as they produce OH negative ions in dissociation in aqueous solution
<u>Lewis </u><u>definition </u>
According to Lewis
- Acids are those substances which have the ability to lose electrons that is they are electron donors.
Example of bases
- Ca(OH)2 :- Calcium hydroxide
- NaOH :- Sodium hydroxide
- KOH :- Potassium hydroxide
[ Note :- There are so many Lewis acids and bases but they are not Arrhenius or Lowry acids or bases ]
<h3><u>Basic </u><u>characteristic </u><u>of </u><u>salt </u></h3>
- Salts are the ionic compounds which are composed of acids and bases that cation and anion
- Salts are generally found in oceans and seas in the forms of crystals
- As they are composed of acids and bases so they are neutral in nature but the salt of strong acid or weak base is acidic in nature or vice versa
- Salts are also good conductor of electricity as they form ionic bond
- Generally, All salts are soluble in water.
- The PH of common Salt is 7
Example of salts
- NH4Cl :- Ammonium chloride
- CuSO4 :- Copper sulphate
- NaCl :- Sodium chloride
A. Sugar... Because the others are mixes of things and combinations. Sugar is pure and on its own.
I hope this helps!
Answer:
76,6 kg
Explanation:
A kg it's equal to 1x10^3 grams
A Gigagrams it's equal to 1x10^9 grams
Knowing this, a kg it's equal to 1x10^6 gigagrams
![7,66*10^{-5}[gigagram]*\frac{1*10^6 [kg]}{1 [gigagram]}= 76.6 [kg]](https://tex.z-dn.net/?f=7%2C66%2A10%5E%7B-5%7D%5Bgigagram%5D%2A%5Cfrac%7B1%2A10%5E6%20%5Bkg%5D%7D%7B1%20%5Bgigagram%5D%7D%3D%2076.6%20%5Bkg%5D)