Tag: p- block elements-ii

Quizzes (21) Questions (408)

Questions Related to p- block elements-ii

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

State True or False.
Before 1961, the atomic weight standard for elements was based on oxygen and not carbon.

  1. True

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

True.

Before 1961, oxygen was used as the reference standard, with an assigned value of 16. The unit of atomic mass was thereby defined as $ 1/16$ the mass of an oxygen atom.

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

The most abundant non-metal in the earth's crust is:

  1. chlorine

  2. hydrogen

  3. silicon

  4. oxygen
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Aluminium is the first most abundant metal while iron is the second most abundant metal on earth. It is the fourth most common element in the earth's crust. Oxygen is the most abundant non metal and second is silicon present on earth's crust.

Multiple choice chemistry p- block elements-ii group 16 elements - general properties group 16 elements - trends in chemical properties group 16 elements

Statement 1: By mass, oxygen is the most abundant element in the human body.
Statement 2: It is principally found as $O _2$ in the bloodstream.

  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

By mass, oxygen is the most abundant element in the human body.

Oxygen is found in the human body as oxy-haemoglobin in the bloodstream but not as $O _2$

So statement 1 is correct but not 2.
Hence option C is correct.
Multiple choice oxoacids of halogens p- block elements-ii p-block elements the p-block elements chemistry

Which of the following is used to prepare $Cl _{2}$ gas at room temperature from concentrated $HCl$?

  1. $MnO _{2}$
  2. $H _{2}S$
  3. $KMnO _{4}$
  4. $Cr _{2}O _{3}$
Reveal answer Fill a bubble to check yourself
A,C Correct answer
Explanation

Manganese dioxide($MnO _2$) is heated with concentrated $HCl$ to form $Cl _2$

$MnO _2+4HCl\rightarrow MnCl _2+Cl _2+2H _2O$

 $HCl$ in action with potassium permanganate gives $C _2$

$2KMnO _4+16HCl\rightarrow 2KCl+2MnCl _2+8H _2O+5Cl _2$.

Hence option A and C is correct.

Multiple choice oxoacids of halogens p- block elements-ii p-block elements the p-block elements chemistry

Which of the following statements is not correct?

  1. All the oxides of halogens are powerful oxidants.

  2. The compounds of oxygen and fluorine are not called oxides but fluorides.

  3. Oxygen fluorides form oxoacids.

  4. In oxyhalides, bonds are mainly covalent due to small difference in electronegativity of oxygen and halogens.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Oxygen florides forms $HF,O _2$ on hydrolysis.

$OF _2 + H _2O\rightarrow O _2 + 2 HF$

$2O _2F _2 + 2H2O\rightarrow O _2 + 4HF$

so oxygen florides do not form forms hypohalous acids.

So the given statement oxygen florides forms oxoacids is wrong.

Hence option C is correct.

Multiple choice oxoacids of halogens p- block elements-ii p-block elements the p-block elements chemistry

Bleaching powder and bleach solution are produced on a large scale and is used in several house-hold products. The effectiveness of bleach solution is often measured by iodometry. Bleaching powder contains a salt of an oxoacid as one of its components. The anhydride of that oxoacid is:

  1. $Cl _{2}O$
  2. $Cl _{2}O _{7}$
  3. $ClO _{2}$
  4. $Cl _{2}O _{6}$
  5. $Cl _2O _3$
  6. $Cl _2O _5$
  7. $Cl _3O _9$
  8. $Cl _3O _5$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bleaching powder is $Ca(OCl)Cl$.


So, bleaching powder contains a salt of $HOCl$.

$Cl _2O$ is an anhydride of $HOCl$.

$Cl _2O+H _2O\Rightarrow 2HOCl$.

Hence, option A is correct.