Reactions of NaOH with Aluminium Metal and HCl
1)When sodium hydroxide reacts with aluminium metal:  
  

2)Which gas is liberated when aluminium metal reacts with a solution of sodium hydroxide?  
  

3)Al2O3 + 2NaOH → …… + H2O  
  

4)Generally metals react with acids to give salt and hydrogen gas. Which of the following acids does not give hydrogen gas when reacting with metals (except Mn and Mg)?  
  

5)The metal which produces hydrogen gas on reaction with dilute hydrochloric acid as well as sodium hydroxide solution is  
  

6)Metals generally react with dilute acids to produce hydrogen gas. Which one of the following metals does not react with dilute hydrochloric acid?  
  

7)What is formed when zinc reacts with sodium hydroxide?  
  

8)What are amphoteric metals?  
  

9)Which of the following metals is not amphoteric in nature?  
  

10)A metal M does not liberate hydrogen from acids but reacts with oxygen to give a black colour product. Identify black coloured product is: