Question:
The substance used as a smoke screen in war fare is
The substance used as a smoke screen in war fare is
Updated On: Apr 17, 2024
- $ SiCl_4$
- $PH_3$
- $PCl_5$
- acetylene
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The Correct Option is B
Solution and Explanation
Actually, $P H _{3}$ is formed there along with acetylene under the reaction of $C a _{3} P _{2}$ with $C a C _{ 2 }$ where, the phosphene reacts with acetylene formed and catches fire to get smoke which forms the smoke screen. In Holme's signal, the calcium phosphide and calsium carbide is thrown in sea where the reaction produces phosphene gas and acetylene and the phosphene catches fire with acetylene and forms smoke which sends the signal.
$C a _{3} P _{2}+ C a C _{2}-$ sea $\rightarrow\left\{ C _{2} H _{2}+ P H _{3}\right\}$
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Concepts Used:
P-Block Elements
- P block elements are those in which the last electron enters any of the three p-orbitals of their respective shells. Since a p-subshell has three degenerate p-orbitals each of which can accommodate two electrons, therefore in all there are six groups of p-block elements.
- P block elements are shiny and usually a good conductor of electricity and heat as they have a tendency to lose an electron. You will find some amazing properties of elements in a P-block element like gallium. It’s a metal that can melt in the palm of your hand. Silicon is also one of the most important metalloids of the p-block group as it is an important component of glass.
P block elements consist of:
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- Group 16 Elements: Oxygen family
- Group 17 Elements: Fluorine family
- Group 18 Elements: Neon family