4. Elements, Compounds and Mixtures

1. Which compound is formed by atoms from two different elements chemically bonded together?

2. Gold has a density of 19.3 g/cm³. If a block of gold has a mass of 9.65 g, what is the volume of this block of gold?

3. The table below shows the property of four substances A to D. Which substance is a metal?

Substance	Melting point (in degree)	Density	Electrical conductivity
A	450	1.2	Poor
B	1500	2.4	Good
C	-60	0.23	Poor
D	2350	3.5	Poor

4. Which diagram shows a mixture of different?

5. Which statement about a mixture is not correct?

6. How many elements are found in a particle of KMnO4?

7. Which element can be found in distilled water?

8. Which of the following contents only mixtures?

9. Which of the following feature is shared between brass and copper?

10. Which of the following would boil over a wide range of temperatures?

11. The table shows the chemical formulae of the three substances.

Substance	Chemical Formula
Nitrogen	N2
Hydrogen	H2
Ammonia	NH3

The word equation shows the reaction between these three substances. nitrogen + hydrogen → ammonia which of the following can be used to represent nitrogen, hydrogen, and ammonia molecules?

12. The table below shows the masses of three elements.

The chemical symbol of elements	H	S	O
Maa of elements	1	32	16

Sulfuric acid has a chemical formula of H2SO4. what is the ratio of the constituent elements by mass in this compound?

	H	S	O
A	1	16	32
B	2	8	16
C	1	32	16
D	2	16	8

13. Which of the following method can be used to differentiate one type of element from the other? I. Melting point II. Boiling point III. Density IV. Colour

14. Which of the following statements about elements is not correct?

15. The table below shows the message of four elements.

The chemical symbol of elements	H	C	S	O
Maa of elements	1	12	32	16

Which compound contains the ratio of the constituent element by mass of 3: 8?

	Compounds	Chemical formula
A	carbon monoxide	CO
B	sulfur dioxide	SO2
C	ethane	C2H6
D	carbon dioxide	CO2

16. Which statement is not correct after sugar crystals dissolved in water to form sugar solution?

17. Which characteristic can be used to identify metal conclusively from non-metals?

18. Study the list of four substances given below. Water Magnesium oxide Carbon dioxide Sugar Which of the following statements is not related to these four substances?

19. Which element is most likely found in the Antacids to neutralize excess acid in the stomach?

20. The diagram below shows the observation of the appearance of our powdered iron and sulphur placed in a test tube before and after heating. Which of the following is correct?

	Diagram 1	Diagram 2
A	A mixture of compound	A compound
B	A mixture of elements	A mixture  of elements
C	A mixture of compound	A mixture  of elements
D	A mixture of elements	A compound

21. Which of the following statement is not correct about the properties of nonmetals?

22. Which of the following is not an example of alloy?

23. When iron is exposed to air and water, it combines with oxygen to form iron oxide known as rust. Which of the term best describes the formation of rust?

24. Which of the following is used to make brass?

25. Magnesium is burnt in air to form magnesium oxide. Which statement is correct?

26. Which of the following substances is not a compound?

27. Which of the following physical properties can be used to describe metals? I. Shiny II. Malleable III. Non-sonorous IV. High melting points

28. Which of the following element is the more abundant in the air?

29. Which of the following set contains only an element?

30. Which of the following statement is true?