Section-A Chemistry (Mark- 26) 1. Why is HF a polar molecule? 1 2. How are kernels held together in a metal? 1 3. Write the balanced equation for the reaction between sodium hydroxide and sulphuric dioxide. 1 4. What chemical change is expected in the air when lightning occurs during thunderstrom? 1 5. What is an alloy? Give one important advantage of an alloy over its components? 2 6. Take about 10 ml of dil Na 2 CO 3 solution in a beaker. Add two drops of methy orange indicator into it. What is the colour of the mixture? Now add dil HCl solution drop by drop into the beaker till the effervescence stops. Add a few more drops of dil HCl. What will be the colour of the solution now? 2 7. What are the word root, primary suffix, secondary suffix and secondary prefix of 2-chloroethanol? 2 8. Draw a proportionate structure of graphic showing the bond together. 2 9. Describe the preparation of soap from fat. Write the relevant chemi