Which of the following formula is that of a dicarboxylic acid?
- A. (CH3CH 2)2CHCOOH
- B. CH2(OH)2
- C. CH3CH(OH)COOH
- D. CH2(COOH)2
- E. CH3COCOOH
Brass is an alloy of copper and
- A. iron
- B. chromium
- C. zinc
- D. tin
- E. magnesium
CH2 = CH2 + H2SO4 → CH3 – CH2 -OSO3H. The reaction illustrated by the equation above is an example of
- A. substitution
- B. oxidation
- C. reduction
- D. addition
- E. displacement
Which of the following elements can from more than one acidic oxide?
- A. Hydrogen
- B. Sulphur
- C. Carbon
- D. Alumium
- E. Iron
Which of the processes represented by the following equations has the greatest positive entropy change?
- A. C6H3(l) → C6H 6 (g)
- B. H2O (s) → H2O(l)
- C. CuO(s) + H2(g) → Cu(s) + H2
- D. Na2CO3(s) + nH2O(l) →Na 2CO3nH2O(s)
- E. S(s) → S(l)
What is the amount (in mole) of sodium trioxocarbonate (IV) in 5.3 g of the compound? (Na2CO3 = 106)
- A. 0.05
- B. 0.10
- C. 0.20
- D. 0.50
- E. 2.00
When air is passed through a heated tube containing finely divided copper, the component that is absorbed in the process is
- A. carbon (IV) oxide
- B. nitrogen
- C. oxygen
- D. water vapour
- E. noble gases
The separation of a mixture of calcium trioxocarbonate (lV) and sodium trioxocarbonate (IV) is most easily carried out by using the differences in their
- A. physical states
- B. melting points
- C. Rf. values
- D. solubility
- E. boiling points
In which of the following is the oxidation number of nitrogen zero?
- A. SO2 and NH3
- B. NaNO3
- C. HNO2
- D. NOI3
- E. N2
The metal extracted from cassiterite is
- A. calcium
- B. copper
- C. tin
- D. sodium
- E. lead