Advertisements
Advertisements
प्रश्न
Name two particles found inside the nucleus. What are they collectively called ?
Advertisements
उत्तर
Protons and Neutrons. Mass number.
APPEARS IN
संबंधित प्रश्न
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?
MATCH THE COLUMNAS
| 1. Jpham Dalton | a. Neutrons |
| 2. Atom | b. Model of the atom |
| 3. Chadwick | c.The atomic theory of matter |
| 4. Rutherfrod | d. Positively charged |
| 5. Protons | e. Electricity neutral |
| 6. Nuclear fusion | f. Generator of electricity |
| 7.Gamma -rays | g. High penetrating power |
| h.Energy in sun |
TRUE \ FALSE
Elements having a tendency to accept electrons are called metals
ANSWER IN DETAIL
How are isobars different from isotopes ?
Name the particles which revolve around the nucleus.
Name three non-metals/radicals which have valency -1, -2, and -3.
Fill in the blank
If an atom loses an electron, it acquires ______ a charge.
What are the building blocks of matter ?
An atom of an element X may be written as `""_9^4"X"`
(a) What does the figure 9 indicate?
(b) What does the figure 4 indicate?
(c) What is the number of protons in atom X?
(d) What is the number of neutrons in atom X?
(e) What is the number of electrons in atom X?
(f) How many electrons are there in the outermost shell of an atom of element X?
(g) Write the symbol of ion formed by an atom of element X.
Which has more atoms, 50 g of aluminium or 50 g of iron ? Illustrate your answer with the help of calculations.
(Atomic masses : Al = 27 u ; Fe = 25 u)
In what respects do the three isotopes of hydrogen differ? Give their structures.
State the meaning of the term – (a) atom, (b) molecule, (c) radical – with a suitable example.
Select the correct answer to the statement given below:
The smallest particle of a substance – capable of independent existence and which retains the characteristics of the substance.
Rewrite the given sentence in correct form.
Elements contain two or more kind of atoms and compounds contain only one kind of atom.
Draw the structure of an atom and explain the position of 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.
In all atoms of an element
Atoms of different elements having ______ mass numbers, but ______ atomic numbers are called isobars.
The graphite refill used is pencil is made of element called ______.
______ is a substance that is made up of three oxygen atoms chemically combined.
