Reaction of Acids with Metals

Q. How many elements from the following can react with hydrochloric acid?
Na, Mg, K, Al, Zn, Ca, Ag, Pt, Cu.

1. 6

Q.

_______ is a colourless gas which is produced by the reaction of active metal with dilute hydrochloric acid.

1. Oxygen

2. Water gas

3. Nitrogen

4. Hydrogen

Q. Which of the following gas is formed when an acid reacts with a metal?

1. Hydrogen
2. Nitrogen
3. Chlorine
4. Oxygen

Q. Write the chemical equations for the following activities. (EX.Q.8.e)
Dilute HCl was poured on baking soda.

Q. X + Dilute acid ---> Salt + Hydrogen gas. X cannot be

1. Zinc
2. Magnesium
3. Sodium
4. Gold

Q. Dilute $HCl$ does not react with $Cu$ but dilute $H{NO}_3$ reacts with $Cu$. Give reason.

1. $H{NO}_3$ is a good oxidising agent
2. $HCl$ is a good oxidising agent
3. $HCl$ is a weak acid
4. $H{NO}_3$ is a strong acid

Q.

Which of the following metals give hydrogen gas with steam acid and caustic alkalis?

1. Pb

2. Mg

3. Fe

4. Zn

Q. Name the gas evolved when dilute hydrochloric acid reacts with sodium hydrogen carbonate. How is it recognised?

Q.

How will you test for the gas which is liberated when hydrochloric acid reacts with an active metal?

Q.

Which of the following reaction is possible

1. ${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Cu}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{CuO}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$

2. ${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Hg}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{HgO}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$

3. ${\mathbf{Fe}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{3}\mathbf{Al}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\stackrel{\mathbf{∆}}{\mathbf{\to }}\mathbf{}{\mathbf{Al}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{3}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{2}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}$

4. None of these