Chemistry
Grade-9
Easy
Question
How many different elements are represented in the compound?
C13H9N.
- 2
- 3
- 1
- 4
Hint:
There are 13 carbons , 9 hydrogens and 1 nitrogen.
The correct answer is: 3
In the periodic table there are 118 elements, each has a designated symbol. In chemical formula symbols are used followed by the number of times each elements occurs in that compound in the subscript.
In the formula C13H9N. There are 13 carbons , 9 hydrogens and 1 nitrogen. Hence, 3 elements are re presented in the compound.
Related Questions to study
Chemistry
When atoms react with one another, sometimes they gain or lose _______________.
When atoms react with one another, sometimes they gain or lose _______________.
ChemistryGrade-9
Chemistry
Electrons in the outermost energy level (farthest from the nucleus) have the most energy and are called ______________.
Electrons in the outermost energy level (farthest from the nucleus) have the most energy and are called ______________.
ChemistryGrade-9
Chemistry
Elements are identified by how many protons are in the nucleus of their atoms. The number of protons can be found on the Periodic Table and is called:
Elements are identified by how many protons are in the nucleus of their atoms. The number of protons can be found on the Periodic Table and is called:
ChemistryGrade-9
Chemistry
Each ___________ is made up of a unique type of __________.
Each ___________ is made up of a unique type of __________.
ChemistryGrade-9
Chemistry
How do bonds tend to form between nonmetals?
How do bonds tend to form between nonmetals?
ChemistryGrade-9
Chemistry
How do bonds tend to form between metals and nonmetals?
In NaCl, Na is a metal and Cl is a non metal.
How do bonds tend to form between metals and nonmetals?
ChemistryGrade-9
In NaCl, Na is a metal and Cl is a non metal.
Chemistry
What determines the reactivity of an element?
What determines the reactivity of an element?
ChemistryGrade-9
Chemistry
How many valence electrons are elements trying to reach in their outer shells?
How many valence electrons are elements trying to reach in their outer shells?
ChemistryGrade-9
Chemistry
How would you describe reactivity on the Periodic Table?
How would you describe reactivity on the Periodic Table?
ChemistryGrade-9
Chemistry
With which element will Hydrogen most likely bond?
With which element will Hydrogen most likely bond?
ChemistryGrade-9
Chemistry
Maximum covalency of Nitrogen is
Maximum covalency of Nitrogen is
ChemistryGrade-9
Chemistry
Electrons that involve in bond formation are
Electrons that involve in bond formation are
ChemistryGrade-9
Chemistry
All elements in the Halogen family react violently because
All elements in the Halogen family react violently because
ChemistryGrade-9
Chemistry
Where are the transition metals found on the periodic table?
Where are the transition metals found on the periodic table?
ChemistryGrade-9
Chemistry
How many elements are in the Noble Gas family?
How many elements are in the Noble Gas family?
ChemistryGrade-9
