Chemistry
Which of the following observations correctly shows the action of indicator on sodium hydroxide solution?
| Indicator | methyl orange | phenolphthalein | |
|---|---|---|---|
| 1. | P | orange to yellow | remains colourless |
| 2. | Q | orange to pink | remains colourless |
| 3. | R | orange to yellow | colourless to pink |
| 4. | S | remains orange | remains pink |
Related Questions
The diagram shown is a wrong attempt to electroplate a pan with copper:
Which of the following could have been done to copper plate a pan?
- To change DC to AC.
- To change the electrolyte from copper sulphate to cobalt sulphate.
- Connect the pan to the negative electrode.
- To induce a higher current.
During the extraction of aluminium by Hall Heroult’s process, the carbon rods are replaced continuously. This is because:
- It minimises heat loss by radiation.
- It enhances the mobility of ions.
- The carbon anode is consumed.
- It lowers the fusion point.
When electrolysis of molten lead bromide is carried out, the products formed at the respective electrodes are:
At the positive electrons At the negative electrode 1. Bromine Lead 2. Bromine Hydrogen 3. Lead Bromine 4. Lead Oxygen The following are the structural diagrams of certain hydrocarbons:
Which two structures are related to each other?
- A and B
- B and C
- C and D
- A and C