Which of the following statements is not correct? The 4s orbital

• A. is defined by the quantum number 1 = O
• B. is of higher energy than the 3d orbital
• C. contains a maximum of two electrons
• D. is spherical about the nucleus

(a) Name the crystalline allotrope of sulphur that is stable at room temperature.

(b)(i) Give one example of a fuel that contains significant amount of sulphur as an impurity.

(ii) State one environmental disadvantage of using a fuel that has high sulphur content

Which of the following pH values is likely to be that of a slightly alkaline solution?

• A. 2
• B. 5
• C. 7
• D. 8

Which of the following accounts for the difference in the mode of conduction of electricity by metals and aqueous salt solutions?

• A. Electrons are present in metals but not in salt solutions
• B. Metals are conductors while salts are electrolytes
• C. Electricity is carried by mobile elrctrons in metals but by ions is aqueous salt solution
• D. salts ionize in aqueous solutions while metals do not

If the volume of a given mass of gas at 298 K and pressure of 205.2 x 103 Nm^-2 is 2.12dm³, what is volume of the gas at s.t.p? (Standard pressure = 101.3 x 103 Nm^-2Standard temperature = 273K)

• A. 39.3dm³
• B. 22.4dm³
• C. 4.93dm³
• D. 3.93dm³

Which of the following minerals contains flurine as one of its constituent elements?

• A. Cryolite
• B. Bauxite
• C. Potash alum
• D. Kaolin

The maximum number of electrons that can accommodated in the shell having the principal quantum number 3 is

• A. 3
• B. 9
• C. 10
• D. 18

Which of the following groups contains entirely linear molecules?

• A. H2NH3O2
• B. CO2NH3
• C. H2CH4N2
• D. CO2H2N2

Which of the following compounds is not correct about the reaction of sodium material for the manufacture of plastics?

• A. Ethyne
• B. Ethane
• C. Monochloroethene
• D. Propene

(a) What is meant by the term acid salt? Give one example.

(b) State the reason why an all-glass apparatus must be used for the laboratory preparation of concentrated trioxonitrate (V) acid.