You are provided with solution W and solid X. Do the following tests recording all of your observations at each stage. Tests on solution W

1. (a)Put 1 cm depth of W into a boiling tube. Add 1 cm depth of aqueous sodium hydroxide. Gently warm the mixture. Test the gas given off. Describe the test and its result. Identify the gas. Keep the mixture for use in (b). test for gas and result ................................................................................................................................................ identity of gas ................................................................................................................................................[3]
2. (b)Add 2 cm depth of dilute nitric acid to the mixture from (a). Then add 1 cm depth of aqueous barium nitrate. Record your observations. ................................................................................................................................................................................... ...................................................................................................................................................................................[1]
3. (c)Identify the cation and the anion in W. cation ............................................................ anion .................................................................[2]
4. (d)Put one of the samples of X into a boiling tube and use a measuring cylinder to add 7cm³ of dilute nitric acid. Record your observations. Test the gas given off. Describe the test and its result. Identify the gas. Keep the mixture for use in (e) and (f). observations ............................................................................................................................................................ ................................................................................................................................................................................... test for gas and result ................................................................................................................................................ identity of gas ................................................................................................................................................[4]
5. (e)Use a measuring cylinder to transfer 2cm³ of the mixture from (d) into a test-tube. Add aqueous sodium hydroxide drop by drop until a change is seen. Then add a further 2 cm depth of aqueous sodium hydroxide. Record your observations. ................................................................................................................................................................................... ...................................................................................................................................................................................[2]
6. (f)Use a measuring cylinder to transfer 2 cm³ of the mixture from (d) into a test-tube. Add aqueous ammonia drop by drop until a change is seen. Then add more aqueous ammonia until a further change is seen. Record your observations. ................................................................................................................................................................................... ................................................................................................................................................................................... ...................................................................................................................................................................................[3]
7. (g)Identify the cation and the anion in X. cation ............................................................ anion .................................................................[2]