Elements
Elements
Element term “element” was first used by Robert Boyle in 1661. An element is a pure substance which cannot be split into two or more simpler substances by any physical or chemical means. It is the simplest form of matter. Copper, iron, gold, hydrogen, oxygen, nitrogen and chlorine are examples of elements. At present, more than 118 elements are known. Out of these 92 are natural elements and others are man made. Hydrogen is an element because it cannot be split into two or more simpler substances by any physical or chemical method. Water is not an element because it can be split into two simpler substances (hydrogen and oxygen) by passing an electric current through it.
Classification of elements:
Elements can be broadly divided into two categories— metals and nonmetals. There is also a third category of elements called metalloids. Such elements have properties lying between those of metals and nonmetals. Boron, silicon and arsenic are examples of metalloids.
Metals have Lustre or Shine:-
They are good conductors of heat and electricity. They are malleable and ductile in the solid state. Most metals are solid at room temperature, except mercury which is a liquid. Examples of metals are sodium, zinc, copper, gold, iron and aluminium.
Nonmetals usually lack lustre and are bad conductors of heat and electricity. They are generally gases, and those that are solid are soft and brittle. Bromine is the only example of a liquid nonmetal. Examples of nonmetals are hydrogen, oxygen, nitrogen, sulphur and phosphorus.
Metalloids have properties intermediate between those of metals and nonmetals. Silicon, boron, arsenic, antimony, bismuth, germanium, etc., are metalloids.
Oxygen is an Element:
No other element has yet been found to be present in oxygen. When pure oxygen is made to react with pure hydrogen, only water is formed. Hence, oxygen is considered to be an element.
Which of the following is not considered as pure substance ? | |||
| Right Option : D | |||
| View Explanation | |||
Which of the following are correct : (a) An element is a pure substance which cannot be split into two or more simpler substances by any physical or chemical means. (b) Copper, iron, gold, hydrogen, oxygen, nitrogen and chlorine are examples of elements. (c) Element term “element” was first used by Robert Boyle in 1661. | |||
| Right Option : D | |||
| View Explanation | |||
Antimony and arsenic can be classified as _________________ | |||
| Right Option : C | |||
| View Explanation | |||
Students / Parents Reviews [10]
It was a good experience with Abhyas Academy. I even faced problems in starting but slowly and steadily overcomed. Especially reasoning classes helped me a lot.
Cheshta
10thI have spent a wonderful time in Abhyas academy. It has made my reasoning more apt, English more stronger and Maths an interesting subject for me. It has given me a habbit of self studying
Yatharthi Sharma
10thIt was good as the experience because as we had come here we had been improved in a such envirnment created here.Extra is taught which is beneficial for future.
Eshan Arora
8thMy experience with Abhyas academy is very good. I did not think that my every subject coming here will be so strong. The main thing is that the online tests had made me learn here more things.
Hiya Gupta
8thA marvelous experience with Abhyas. I am glad to share that my ward has achieved more than enough at the Ambala ABHYAS centre. Years have passed on and more and more he has gained. May the centre flourish and develop day by day by the grace of God.
Archit Segal
7thMy experience was very good with Abhyas academy. I am studying here from 6th class and I am satisfied by its results in my life. I improved a lot here ahead of school syllabus.
Ayan Ghosh
8thIt has a great methodology. Students here can get analysis to their test quickly.We can learn easily through PPTs and the testing methods are good. We know that where we have to practice
Barkha Arora
10thAbhyas Methodology is very good. It is based on according to student and each child manages accordingly to its properly. Methodology has improved the abilities of students to shine them in future.
Manish Kumar
10thMy experience with Abhyas is very good. I have learnt many things here like vedic maths and reasoning also. Teachers here first take our doubts and then there are assignments to verify our weak points.
Shivam Rana
7thAbhyas is a complete education Institute. Here extreme care is taken by teacher with the help of regular exam. Extra classes also conducted by the institute, if the student is weak.
