COMPETENCY BASED
(PISA BASED QUESTIONS)
chapter :-12
1. .
A student is given a mixture of iron filings and sulphur in thee ratio 1 : 2 by weight. He was then asked to heat the mixture over a flame and to observe the olor change. The student will observe that the mixture becomes:
.
black"
(iv) milk".
3. White gold is used in jewelry and contains two elements, gold and palladium. A jeweler has two different samples that are both identical in appearance and have a uniform composition throughout. What can be said about the samples? .
. They are homogeneous mixtures and be classified as metallic alloys..".
Are different kinds of atoms chemically combined with each other? ".
5.Which of the following is considered to be a pure substance? .
Sodium chloride".
6. A sample contains two substances and has uniform properties. The sample is::
.
part :- i
chapter :-12
class 9
1. .
A student is given a mixture of iron filings and sulphur in thee ratio 1 : 2 by weight. He was then asked to heat the mixture over a flame and to observe the olor change. The student will observe that the mixture becomes:
.
black"
2. Which of the following is an example of a heterogeneous substance?:.
(iv) milk".
3. White gold is used in jewelry and contains two elements, gold and palladium. A jeweler has two different samples that are both identical in appearance and have a uniform composition throughout. What can be said about the samples? .
:
. They are homogeneous mixtures and be classified as metallic alloys..".
4. Compounds:. :
Are different kinds of atoms chemically combined with each other? ".
5.Which of the following is considered to be a pure substance? .
Sodium chloride".
6. A sample contains two substances and has uniform properties. The sample is::
.
.
... Answer is iv)
A homogeeous mixture ".
7. Which one of the following will result in the formation of a mixture? .
Adding milk in water".
8. .In which of the following the constituents are present in any ratio?.
mixture.".
9. Air is regarded as a mixture because: .
(iv)Its composition may vary.".
10. Which of the following is a compound? .
Hydrogen sulphide".