Advertisements
Advertisements
प्रश्न
Define the following term with an example.
Element
Advertisements
उत्तर
Element: It is a substance that cannot be broken down into simpler substance by chemical means
Ex.: Oxygen, Hydrogen, Gold & Helium.
APPEARS IN
संबंधित प्रश्न
If bromine atom is available in the form of, say, two isotopes `""_35^79Br (49.7%)" and """_35^81Br (50.3%)`, calculate the average atomic mass of bromine atom.
The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes `""_8^16X" and """_8^18X` in the sample?
Define:- Radicals
Write the names of the elements present in the:-
Ammonia
Write the names of `"Ca"("NO"_3)_2` compounds :
Name two particles found inside the nucleus. What are they collectively called ?
Write electronic configuration of oxygen, fluorine, sodium, silicon, argon.
Name the particle or particles you would expect to find in :
The nucleus of an atom
Fill in the blank
If an atom loses an electron, it acquires ______ a charge.
Name the unit in which the radius of an atom is usually expressed.
Fill in the following blanks with suitable words :
In water, the proportion of oxygen and hydrogen is .............. by mass.
An atom of element E contains 3 protons, 3 electrons and 4 neutrons :
(a) What is its atomic number?
(b) What is its mass number?
(c) Write the electronic configuration of the element E.
(d) State whether element E is a metal or non-metal. Why?
(e) What type of ion, cation or anion, will be formed by an atom of element E? Why
(f) Write the symbol of the ion formed by an atom of element E.
(g) What could element X be?
Which of the following statement is correct about the atom of an element ?
A radical take part – unsplit in a chemical reaction and retains its identity in reactions.
With reference to the radical –
- ammonium
- bisulphate
- carbonate
state the group of atoms present in each radical.
State true or false. If false, correct the statement.
An atom is electrically neutral.
Which of the following statements made by Dalton has not undergone any change?
Define the term ions or radicals.
The volume occupied by 4.4 g of CO2 at S.T.P ______
Atoms of one element can be transmuted into atoms of other elements by ______
A small block slides down on a smooth inclined plane, starting from rest at time t = 0. Let Sn be the distance travelled by the block in the interval t = n – 1 to t = n. Then, the ratio `S_n/(S_(n + 1))` is ______.
