Which of the following is not an allotrope of carbon?

Correct Answer: An ion

Explanation:

An electrically charged atom or group of atoms formed by the loss or gain of one or more electrons is called an Ion.

Cation:

An ion is a cation (positive ion) if it is created by electron loss and is attracted to the cathode in electrolysis.

Anion:

An ion is an anion (negative ion) if it is created by an electron gain and is attracted to the anode.

 

The valence of an ion is equal to the number of electrons lost or gained and is indicated by a plus sign for cations and a minus sign for anions.

Ex: Na +, Cl?, Ca ++,...

Correct Answer: copper(II) hydroxide

Explanation:

Sodium chloride:

The solubility rules tell you that all halides are soluble with the exception of those formed with siver, mercury, and lead ions. Since this is not the case here, sodium chloride will be soluble.

 

Silver nitrate:

It is soluble because all nitrates are soluble, without exception.

 

Potassium sulfate:

It is soluble because all sulfates are soluble with the exception of those formed with silver, calcium, barium, mercury, lead, and strontium ions.

 

Copper (II) hydroxyde:

It is insoluble because all hydroxides are insoluble with the exception of those formed with alkali metal ions and barium.

Correct Answer: We know that polar substances are soluble in polar solvents and non polar substances are soluble in non-polar solvents only Here the hydrocarbons are non-polar molecular substances and water is a polar solvent So water can't dissolve hydrocabons Hence, as hydrocarbons are non-polar substances, they are insoluble in water as it is a highly polar solvent

Correct Answer: Both A & B

Explanation:

An Element is a pure substance of one type of atom. In chemistry, any material such as carbon, hydrogen, iron, or oxygen that cannot be broken down into more fundamental substances is nothing but an element.

Correct Answer: 6CO2 + 6H2O -----> C6H12O6 + 6O2

Explanation:

Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms activities.

 

Photosynthesis can be represented using a chemical equation.

 

The overall balanced equation is

 

               $$\begin{gathered} 6 CO 2 + 6 H 2 O ? Sunlight C 6 H 12 O 6 + 6 O 2 \\ S o u r c e o f C a r b o n & O x y g e n + \\ S o u r c e o f E l e c t r o n s & H y d r o g e n + \\ E n e r g y t h a t d r i v e s P h o t o s y n t h e s i s - - - - > \\ S u g a r + G a s p r o d u c e d b y s p l i t t i n g w a t e r . \end{gathered}$$

 

Where 

CO2 = carbon dioxide 

H2O = water

C6H12O6 = glucose 

O2 = oxygen.

Correct Answer: 3' > 2' > 1'> NH3

Explanation:

The order of basicity in ammonia is different in gaseous phases vs. aqueous phases due to hydrogen bonding.

 

So in gaseous phases it's the well known: 3' > 2' > 1'> NH3. Just so we're on the same page, this is due to the inductive effect of electron donating alkyl groups--they destabilize the lone pair on nitrogen atom, making nitrogen more basic.

 

But in aqueous phase, the order is slightly different: 2'> 1'> 3' > NH3.

Correct Answer: 109.9446

Explanation:

The term gram formula mass is synonymous with molecular mass. So, to get this, we must add molar mass of all the elements in this compound.

 

Given compound is Lithium Sulphate -  Li 2 SO 4

Elemental calculation ::

Li  -  Lithium   -   6.941    -     2   -   13.88200 %
S  -  Sulfur     -    32.065   -    1   -   32.065 %
O  -  Oxygen   -   15.9994  -    4   -   63.9976 %

Now, total = 12.6264 + 29.1647 + 58.2090 = 109.9446 

 

Hence, the gram formula mass of Li2SO4 = 109.9446.

Correct Answer: Hexane > Pentane > Propane

Explanation:

The boiling point of the compounds depend on the number of carbons in them. Hexane has 6, Pentane has 5 and Propane has 3 carbons. As Hexane is with 6 carbons it has highest boiling point and next Pentane with 5 and lowest Propane with 3. 

Correct Answer: Tetra-ammine dichloro cobalt (III) chloride

Explanation:

The IUPAC nomenclature in organic chemistry is a systematic method that is used to name organic chemical compounds as recommended by the International Union of Pure and Applied Chemistry (IUPAC).

 

The IUPAC name of the given complex [Co (NH?)?Cl? ]Cl is - Tetra-ammine dichloro cobalt (III) chloride.

 

The complex [Co (NH?)? Cl? ] Cl ionizes an aqueous solution to furnish the chloride ion Cl? and [Co (NH?)? Cl? ] ?.

Correct Answer: Monosaccharides can be classified according to the spatial arrangement of their atoms.

Explanation:

Monosaccharides, also called simple sugars, are the most basic units of carbohydrates. They are fundamental units of carbohydrates and cannot be further hydrolyzed to simpler compounds.

 

Hence, Monosaccharides can be classified according to the spatial arrangement of their atoms is true about Monosaccharides.