School:
WORK-SHEET (1st Month 2020-21)
Subject - Science, Class-IX, Section:
Name:
Roll No.:
(Note: Before submitting the solved paper to the teacher, Student should also note it
down in his/her notebook.)
Attempt all questions. Use separate sheets to solve the worksheet.
[Theme: Materials, Unit I: Matter- It's Nature and Behaviour,
Theme: The World of the Living, Unit II: Organization in the Living World,
Theme: Moving Things, People and Ideas, Unit III: Motion, Force and Work]
1. What is meant by a pure substance?
2. List the point of differences between homogeneous & heterogeneous mixture?
3. Classify the following into elements, compounds & mixture:
a) Sodium b) Soil
c) Sugar Solution d) Silver
e) Calcium carbonate f) Silicon
h) Air i) Soap
k) Carbon dioxide
g) Coal
j) Methane
Answers
1.Pure substances are defined as substances that are made of only one type of atom or molecule. The purity of a substance is the measure of the extent to which a given substance is pure. The physical properties of a pure substance include well-defined melting and boiling points.
2.A homogeneous mixture has the same uniform appearance and composition throughout. Many homogeneous mixtures are commonly referred to as solutions. A heterogeneous mixture consists of visibly different substances or phases. The three phases or states of matter are gas, liquid, and solid.
3.
Classification of the given substances into elements compounds and mixtures:
Elements: Sodium, Silver, Tin and Silicon.
Compounds: Calcium carbonate, Methane and carbon dioxide.
Mixtures: Soil, Sugar solution, Coal, Air, Soap and Blood.