Chemistry Past Questions

3696

(a) An element X is represented as $$^{40}_{20} X$$

(i) How many electrons and how many neutrons are present in the atom of X?

(ii) Write the electronic configuration of the atom

(b) Chlorine, whose atomic number is 17, reacts with the element X to form a compound.

(i) What type of bond is formed between X and chlorine?

(ii) Explain how the bond between X and chlorine is formed

(iii) Write the formula of the compound formed and statelhree properties of the compound.

(c) Chlorine has two isotopes of mass numbers 35 and 37 respectively. Suggest the possible relative molar masses of a chlorine molecule.

(d) Calculate the mass of one atom of carbon, given that one mole of carbon weighs 12.0g. (L = 6.02 x 10$$^{23}$$)

3697

A second alkanol can be oxidized to give an

• A. alkanone
• B. alkyne
• C. alkanoic acid
• D. alkanal
3698

Which of the following will give a precipitate with an aqueous solution of copper (I) chloride?

• A. But-2-ene
• B. But-1-ene
• C. But-2-yne
• D. But-1-yne
3699

The IUPAC name for CH$$_3$$CH$$_2$$COOCH$$_2$$CH$$_3$$ is

• A. methylpropanoate
• B. ethylethanoate
• C. ethylpropanoate
• D. methylethanoate
3700

A certain hydrocarbon on complete combustion at s.t.p produced 89.6dm$$^3$$ of CO$$_2$$ and 54g of water. The hydrocarbon should be

• A. C$$_6$$H$$_6$$
• B. C$$_4$$H$$_{10}$$
• C. C$$_5$$H$$_{10}$$
• D. C$$_4$$H$$_6$$