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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

Elements of which family are in colored gaseous state, in liquid state and with metallic properties.

  1. least-reactive family of elements

  2. alkali metals

  3. halogen family of elements

  4. noble gases

  5. family whose oxides form acids in water
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Elements of halogen family are in colored gaseous state, in liquid state and with metallic properties.
At room temperature, fluorine and chlorine are gases, bromine is a liquid and iodine is a solid.
The colours of fluorine, chlorine, bromine and iodine are yellow, greenish yellow, red and violet.
Iodine has metallic luster.

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

Halogens have similar reactivity because :

  1. they have the same number of protons

  2. they have the same number of electrons

  3. they have similar outer shell electron configurations

  4. they have valence electrons with the same quantum numbers

  5. they have the same number of neutrons
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Halogens have similar reactivity because they have similar outer shell electron configurations of $\displaystyle  ns^2np^5$. 
Thus, all halogens gain one electron to complete octet. Thus, they form uni-negative ion (anion).

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

When a dry solid is treated with a mild oxidizing agent, a purple solid is produced. What is the dry solid?

  1. $N _2$
  2. $KI$
  3. $CCl _4$
  4. $AgNO _3$
  5. $CaCO _3$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A purple solid (iodine) is produced by treatment of the dry solid $KI$ with a mild oxidizing agent. The mild oxidising agent oxidizes iodide ion to iodine.

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

Which form negative ions in an ionic bond?

  1. Alkali metals

  2. Alkaline Earth metals

  3. Noble gases

  4. Halogens

  5. Transition metals
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Halogens have 7 electrons in their valence shell.

They need 1 electron to complete their octet.
Hence, during the formation of ionic bond they accept an electron and form negative ions.

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

Statement $1$: Element $Z$ with an electronic configuration of $1s^{2} 2s^{2} 2p^{5}$ can be expected to form the compound $MgZ _{2}$.
Statement $2$: Each atom of $Z$ needs two electrons to fill its valence shell.

  1. Both Statement $1$ and Statement $2$ are correct and Statement 2 is the correct explanation of Statement $1$
  2. Both Statement $1$ and Statement $2$ are correct, but Statement $2$ is NOT the correct explanation of Statement $1$
  3. Statement $1$ is correct, but Statement $2$ is not correct
  4. Statement $1$ is not correct, but Statement $2$ is correct
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Element Z has electronic configuration ${1s}^2 2s^2 2p^{5}$ , its belongs to 17th group so, it can form compound $MgZ _2$.

Its valency will be one.
It requires 9 elctron to fill its valence shell or it has already 9 electrons. So, statement 2 is wrong.
 

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

Treatment of the dry solid with a mild oxidizing agent produces a purple solid having formula _______.

  1. $N _2$
  2. $KI$
  3. $CCl _4$
  4. $AgNO _3$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Iodine can be displaced from potassium iodide if a more reactive element is made to react with potassium iodide. In the presence of a mild oxidising agent, the iodine ions are oxidised to $I _2$. Iodine is purple in colour.

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

Identify the gas that would form when hydrobromic acid is combined with nickel (II) sulfide.

  1. $NiBr _{2}$
  2. $H _{2}S$
  3. $HBr$
  4. $NiS$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The gas that would form when hydrobromic acid is combined with nickel (II) sulfide is $H _2S$

$2 HBr(aq) + NiS(s)\rightarrow H _2S + NiBr _2$.
Hence option B is correct.
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 most acidic?

  1. $HClO$
  2. $HClO _2$
  3. $HClO _3$
  4. $HClO _4$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

As the oxidation number of chlorine(non metal) increases in the given acids the acidic nature of the compound increases. So the oxidation numbers of chlorine in the given compounds are $+1,+3,5,+7$ respectively.

So the acidic nature of $HClO _4$ is high.
Hence option D is correct.