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Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

Which of the following is basic?

  1. ${ F } _{ 2 }$
  2. ${ Cl } _{ 2 }$
  3. ${ Br } _{ 2 }$
  4. ${ I } _{ 2 }$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Down the group, metallic nature increases. If metallic nature increases, basic nature increases. Among halogens, $I _2$ is at bottom and it has high metallic nature than other halogens. So, it is more basic.

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

Which of the following statements is NOT TRUE?

  1. HF is a stronger acid than HCl

  2. Among Halide ions, iodide is the most powerful reducing agent

  3. Flourine is the only halogen that does NOT show a variable oxidation state

  4. HOCl is a stronger acid than HOBr
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

HF is actually a weak acid compared to other hydrogen halides due to strong hydrogen bonding and high bond dissociation enthalpy, making the statement that HF is stronger than HCl incorrect.

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

The most covalent halide is:

  1. $Al{F} _{3}$
  2. $Al{Cl} _{3}$
  3. $Al{Br} _{3}$
  4. $Al{I} _{3}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

According to Fajans rule larger the size of anion,more covalent will be the bond . So, according to this most covalent halide is iodide as because it is the least electronegative among all the halides,greater size of halide anion,so in a covalent compound it has the least polarising

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

The volatility of the Group $17$ elements, chlorine, bromine and iodine, decreases down the group. What is responsible for this?

  1. Bond length in the halogen molecule

  2. Bond strength in the halogen molecule

  3. Electronegativity of the halogen

  4. Number of electrons in the halogen molecule
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$\text{The volatility of the Group 17 elements decrease down the group due to the increse the numnber of electrons.}$

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry
State whether the given statement is true or false:

In Japan Sunami, there has been increase in radioactive iodine content in salt.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The given statement is True. 
In Japan Sunami, there has been increase in radioactive iodine content in salt.
Traces of iodine are found in mineral deposits. Iodine also finds its way into the animal system as thyroxin in thyroid glands.

Multiple choice group 17 elements - trends in chemical properties group 17 elements - properties p- block elements-ii p-block elements chemistry

In very recent Sunami in Japan, food materials were banned as they were contaminated with radioactivity . Which of the following was found to have radioactive beyond prescribed limit ?

  1. F

  2. Cl

  3. I

  4. At
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Tokyo, the city first reported a spike of radioactive iodine in its water supply on March 23, 2011 at levels below the limit for adults but above the threshold of safety for infants; since then, iodine levels in Tokyo's water have declined below both thresholds. 


Above-limit levels of radioactive iodine and cesium have also been found in milk and vegetables in seven prefectures in Japan. 

Hence,option C is correct.