Advertisements
Advertisements
प्रश्न
What are orbits or shells ?
उत्तर
The fixed circular paths along which electrons revolve round the nucleus.
APPEARS IN
संबंधित प्रश्न
Tick the most appropriate answer.
Who discovered that radioactive rays are given out by uranium?
- Henri Becquerel
- Marie Curie
- Pierre Curie
- Schmidt
WRITE SHORT ANSWER
What is radioactivity?
Define:- Molecule
Define: Relative atomic mass
A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons.
What is such a particle called ?
Name the three subatomic particles present in an atom.
Match the pairs.
| Group 'A' | Group 'B' |
| a. Proton | i. Negatively charged |
| b. Electron | ii. Neutral |
| c. Neutron | iii. Positively charged |
Compare:
Chlorine atom and chloride ion, with respect to
Atomic structure
Electrical state
Draw the basic structure of an atom representing its –
- Subatomic particles
- Nucleus
- Orbits or shells.
State true or false. If false, correct the statement.
The basic unit of an element is molecule.
Assertion: An atom is electrically neutral.
Reason: Atoms have equal number of protons and electrons.
Name the sub-atomic particles.
Project.
To have an idea of what atoms are, students can be asked to construct atoms using pipe cleaners (thin metal wires-electron shells), pompoms (balls-different colours for protons and neutrons) and beads (electrons). Students will love and enjoy putting them together and they look great hanging from the ceiling in the classroom.
An element is composed of ______ atoms.
Atoms of different elements having the same number of ______ are called isotones.
Atoms of one element can be transmuted into atoms of other elements by ______
Does the solubility of a substance change with temperature? Explain with the help of an example.
A sample of vitamic C is known to contain 2.58 ×1024 oxygen atoms. How many moles of oxygen atoms are present in the sample?
The most abundant type of atom is the universe is ______.
What are the 3 most abundant atoms on the earth?
