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Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of sodium and potassium biological importance of elements biological importance of s block elements biological importance of magnesium and calcium

A typical $70$ kg man constitutes $X$ kg of sodium and $Y$ kg of potassium?

  1. $x=90,\ y=70$
  2. $x=90,\ y=170$
  3. $x=70,\ y=90$
  4. $x=170,\ y=90$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Option $(B)$ is correct.

A typical 70 $kg$ man constitutes 90 $kg$ of sodium and  170 $kg$ of potassium.

Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of sodium and potassium biological importance of elements biological importance of s block elements biological importance of magnesium and calcium

Which element is present in blood plasma in larger quantity?

  1. Sodium

  2. Potassium

  3. Iron

  4. Copper
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Option $ (A) $ is correct.
Sodium is present in blood plasma in larger quantity. It is present in extracellular fluid and interstitial fluids.
Hence, even though sodium diffuses into the cell due to the concentration gradient, there is a sodium pump which pushes it back again.
Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of sodium and potassium biological importance of elements biological importance of s block elements biological importance of magnesium and calcium

Which of the following element participate in oxidation of glucose to form ATP?

  1. Calcium

  2. Sodium

  3. Magnesium

  4. Potassium
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Option $(D)$ is correct.
Potassium participates in the oxidation of glucose to form ATP through  ATP-sensitive potassium channel. 
Multiple choice chemistry the s-block elements (alkali and alkaline earth metals) biological importance of sodium and potassium biological importance of elements biological importance of s block elements biological importance of magnesium and calcium

Select the correct statement with respect to sodium peroxide?

  1. It decolourises the $KMnO _4$ solution.
  2. On heating with oxygen at $450^0C$ and 300 atm pressure, it becomes paramagnetic.
  3. It is obtained along with sodium metal when sodium oxide is heated to a temperature more than $400^oC$.

  4. It gives both hydrogen peroxide and oxygen gas with water as well as with sulphuric acid.
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

(A) $2Mn{ O } _4^-(pink)+16H^++5O _2^{2-}\rightarrow 2Mn^{2+}+8H _2O+5O _2$.
(B) $Na _2O _2+O _2\xrightarrow [300 atm]{> 450^oC} 2NaO _2 ({ O } _2^-$ contains on unpaired electron in $\pi^*$ MO).
(C) $2Na _2O\xrightarrow {400^oC} Na _2O _2+2Na$.
(D) Gives only $H _2O _2$.

Multiple choice limestone uses of group 2 compounds group 2 industrial inorganic chemistry chemistry

Following compounds are used in fire-works :

  1. $LiNO _{3}$
  2. $BaCl _{2}$
  3. $(NH _{4}) _{2}Cr _{2}O _{7}$

  4. all of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

All compounds are used in fire works.
$LiNO _{3}$ on ignition imparts crimson red,
                        $BaCl _{2} \rightarrow $ green
           $(NH _{4}) _{2}Cr _{2}O _{7}\rightarrow$ green.

Multiple choice limestone uses of group 2 compounds group 2 industrial inorganic chemistry chemistry

The hydration energy of ${Mg}^{+2}$ is larger than that of ?

  1. ${Al}^{+3}$
  2. ${Na}^{+1}$
  3. ${Be}^{+2}$
  4. ${Mg}^{+3}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hydration energy depends on charge of ion and ionic radius. Higher the charge, greater the hydration energy. On the other hand, smaller the size, greater the hydration energy. Charge is considered first for comparison. Hence, $Mg^{2+}$ has higher hydration energy than $Na^+$.