Page 235 - ICSE Chemistry 8

ATTEMPT AND SCORE

ASSESSMENT SHEET 1

A. Fill in the blanks.
1. ______________ have no fi xed shape or volume.
2. The par cles of ma er are separated by _____________________.
3. The state of ma er is decided on the basis of _____________________ and interpar cle spaces
between the par cles of ma er.
4. Kine c Molecular Theory explains the ______________ of ma er in diff erent states.
5. The total mass during a chemical reac on remains ______________.
6. Changes that occur a er a regular interval of me are called ____________________.
7. ______________ changes are benefi cial to us.
8. A physical change is ______________ and ______________.
9. ______________ is a process by which a substance changes from the liquid state to the solid state
on cooling.
10. The process of forma on of rust on the iron surface is called ______________ of iron.
11. A ______________ is a substance that has a fi xed composi on and fi xed chemical proper es.
12. The cons tuents of a mixture are not present in a ______________ ra o.
13. A ______________ is a type of mixture in which a component is not dissolved completely into
another component is called a ______________.
14. A type of mixture consis ng of two or more immiscible liquids is called an ______________.
15. The method of separa ng components of a mixture using wind or moving air is called ______________.
16. ______________ are the building blocks of ma er and cannot be chemically subdivided by ordinary
means.
17. The number of protons present inside the nucleus of an atom of an element is called its
________________.
18. Atoms of the same element having same atomic number but diff erent mass number are known as
______________.
19. The outermost shell of an atom is called ______________.
20. The elements showing more than one valency are said to have ______________.
21. An _________ is a charged par cle which is formed when an atom or a group of atoms gains or loses
electrons.
22. A molecule of a compound is represented using a ___________________.
23. A ______________ consists of reactants and products.
24. The ______________ states that atoms of the reac ng molecules involved in a chemical reac on do
not change.
25. ______________ is a chemical reac on that occurs in green plants in the presence of light.
26. Substances that take part in a chemical reac on are called ______________.
27. When zinc granules are added to dilute sulphuric acid, ______________ is evolved as a brisk
eff ervescence.
28. The chemical reac on in which heat energy is evolved is called ______________.

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