Chemistry291

  Is potassium dichromate(K2Cr2O7) a Pure Substance? Select one from the following options: A)No  B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. Potassium dichromate (K₂Cr₂O₇) is a compound.So it is a pure substance. Next

Is diamond a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. Diamond is an element.So it is a pure substance.Remember that diamond is formed by only one type of atom which is carbon. Next

Is  milk a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(A) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds. So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. In milk, we get more than one elements and compounds.So milk is neither a single compound nor a single element.As a result, it is not a pure substance.It doesn't have a  definite and fixed composition.Actually,it is a mixture.In milk,we get water, protein,minerals  etc. Next

Is beryllium(Be) a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. Beryllium(Be) is an element.So it is a pure substance. Next

Is oxygen (O₂) a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Oxygen(O₂) is an element.So it is a pure substance. Next

Is lithium (Li) a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Lithium(Li) is an element.So it is a pure substance. Next

Is Hydrogen (H2) a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Hydrogen(H₂) is an element.So it is a pure substance. Next

Is Helium (He) a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Helium(He) is an element.So it is a pure substance. Next

Is  blood a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(A) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds. So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. In blood, we get more than one elements and compounds.So blood is neither a single compound nor a single element.As a result, it is not a pure substance.It doesn't have a  definite and fixed composition.Actually,it is a mixture.In blood,we get N₂,O₂,CO₂, Organic and inorganic compounds etc. Next

  Is  soil a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(A) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds. So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. In soil we get more than one elements and compounds.So soil is neither a single compound nor a single element.As a result, it is not a pure substance.It doesn't have a  definite and fixed composition.Actually,it is a mixture.In soil,we get water,air,organic and inorganic compounds etc. Next

Is a mixture a pure substance yes or no? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(A) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds. So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. Next

Is  air a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(A) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds. So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. In air we get more than one elements and compounds.So air is neither a single compound nor a single element.As a result, it is not a pure substance.It doesn't have a  definite and fixed composition.Actually,it is a mixture.In air,we get N₂,H₂,CO₂ etc. Next

How many sigma and pi bonds are in a single double and triple bond? Today you will learn about the number of sigma and pi bonds that are present  in a single double and triple bond.Let us know the rules first. Rule-1:One single bond indicates one sigma bond. Rule-2:One double  bond indicates one sigma bond and one pi bond. Rule-3:One triple bond indicates one sigma bond and two pi bonds. So ,from second rule, we can say that in a single double we get one sigma and one pi bonds. from third rule, we can say that in a single triple bond we get one sigma and two pi bonds. Next

How many sigma and pi bonds are present in triple bond? Today you will learn the number of sigma and pi bonds that are present in a triple bond. Rule-1:One single bond indicates one sigma bond. Rule-2:One double  bond indicates one sigma bond and one pi bond. Rule-3:One triple bond indicates one sigma bond and two pi bonds. So ,from third rule we can say that we get one sigma and two pi bonds that are present in a triple bond.

Is iron (Fe)  a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds. So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Iron (Fe)  is an element.So it is a pure substance.It has a  definite and fixed composition.All samples of iron (Fe) are chemically identical. Next

Is hydrochloric acid(HCl) a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds. So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Hydrochloric acid(HCl)  is a compound.So it is a pure substance.It has a  definite and fixed composition.All samples of hydrochloric acid(HCl) are chemically identical.Besides,it cannot be physically separated into its  components, H + and Cl- . Next

Is  sulfuric acid(H₂SO₄) a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Sulphuric acid(H2SO4)  is a compound.So it is a pure substance.It has a  definite and fixed composition.All samples of sulphuric acid (H₂SO₄) are chemically identical.Besides,it cannot be physically separated into its  components, H +  and   SO 4 2- Next

Is sodium fluoride(NaF) a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Sodium fluoride (NaF)  is a compound.So it is a pure substance.It has a  definite and fixed composition.All samples of sodium fluoride (NaF) are chemically identical.Besides,it cannot be physically separated into its components,Na+ and F-.

Is sodium iodide(NaI) a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Sodium iodide(NaI) is a compound.So it is a pure substance.It has a  definite and fixed composition.All samples of sodium iodide (NaI) are chemically identical.Besides,it cannot be physically separated into its components,Na+ and I-.

Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Sodium bromide (NaBr) is a compound.So it is a pure substance.It has a  definite and fixed composition.All samples of sodium bromide (NaBr) are chemically identical.Besides,it cannot be physically separated into its components,Na+ and Br-.

Is Gold (Au) a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Gold(Au) is an element.So it is a pure substance. Next

Is Sodium (Na) a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Sodium is an element.So it is a pure substance. Next

Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Explanation: Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Sodium chloride (NaCl) is a compound.So it is a pure substance.Sodium chloride is called table salt.It has a  definite and fixed composition.All samples of sodium chloride (NaCl) are chemically identical.Besides,it cannot be physically separated into its components,Na+ and Cl-.

Is a molecule a pure substance ? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.A molecule can be an element or a compound.So a molecule is a pure substance. Next

Is Carbon monoxide (CO) a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Carbon monoxide is a compound.So it is a pure substance. Next

Is Carbon dioxide (CO2) a pure substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into elements and compounds.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element.Carbon dioxide is a compound.So it is a pure substance. Next

Is an Element a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that an element is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. Next

Is a Compound a Pure Substance? Select one from the following options: A)No B)Yes C)Never D) Sometimes Answer:(B) Matter can be divided into pure substance and mixture.Then pure substance can be divided into element and compound.So from this classification,we can say that a compound is a pure substance.In pure substance,the composition remains fixed.An element is formed by only one type of atoms or by atoms which have same atomic number.On the other hand,a compound is formed by more than one element. Next