A non-metal is found to be solid at room temperature, lustrous, and sublimes on heating. Which non-metal shows this unusual combination of physical properties?
Iodine
Non-metals are usually dull, and many of them are gases at room temperature. Lustre is normally a property of metals, so a lustrous solid non-metal that also sublimes is an exception worth remembering.
Iodine is a violet-black, shiny crystalline solid at room temperature. On gentle heating it changes directly from solid to violet vapour without melting, that is, it sublimes; this is why it is used as a common example of sublimation.
Sulphur is a dull yellow solid that melts on heating instead of subliming. Phosphorus (white or red) is a waxy or powdery solid that is not lustrous.
Carbon in the form of graphite has some lustre, but it does not sublime on ordinary heating; it changes to vapour only at extremely high temperatures, so it does not fit all three properties.
Hence, Iodine.
Similar Questions
Which of the following statements is/are true?
a. The rusting of iron can be prevented by making alloys.
b. Stainless steel is primarily an alloy of iron, chromium, and nickel.
c. An alloy is a heterogenous mixture of two or more metals.
A mining company discovers a new ore containing a metal from the top of the reactivity series. They want to extract this metal efficiently and economically. Which extraction method should they use?
In the electrolytic refining of copper, which material is used as the cathode?
Metals like sodium and aluminium, placed at the top of the activity series, are extracted by:
Which of the following is an effective method to prevent corrosion?
A mining company discovers a new metal that is low in the activity series and is found in its native state. Which extraction method should the company prioritize to obtain the pure metal efficiently?
Which of the following statements describes why metals like gold are found in a free state in nature, while metals like sodium are not?
In reactivity series metals are arranged in decreasing order of their activity. The metal which lies at the top of series is:
What is the main purpose of anodising aluminium during its surface treatment process?
A shipping company needs to ensure their iron cargo ships are protected from corrosion during long voyages through salty ocean water. Which strategy would be most effective for preventing corrosion for this purpose?
Important Questions from Metals & Non-metals
Due to improper/indiscriminate disposal of hold and used computers or their parts, which of the following are released into the environment as e-waste?
1. Beryllium
2. Cadmium
3. Chromium
4. Heptachlor
5. Mercury
6. Lead
7. Plutonium
Select the correct answer using the codes given below:
Recently, there has been a concern over the short supply of a group of elements called 'rare earth metals'. Why?
1. China, which is the largest producer of these elements, has imposed some restrictions on their export.
2. Other than China, Australia, Canada and Chile, these elements are not found in any country.
3. Rare earth metals are essential for the manufacture of various kinds of electronic items and there is a growing demand for these elements.
Which of the statements given above is/are correct?
Which of the following metals CANNOT be cut with a knife?
Which of the following will be formed when dilute hydrochloric acid is added to a beaker having copper oxide ?
Which of the following statement is incorrect regarding metals?
