Hellium argon neon xenon krypton randon oxygen fluorine chlorine bromine
See , from the equation we can see that for forming two mole of H2O 2Mole of H2 has to react.
Mass of 2 Mole H2O is 18*2gm or 36gm.
So for forming 36 gm H2O 2×2 I.e. 4 gm H2 has to take part in reaction.
Therefore, to form 1 gm H2O 4÷36 gm of H2 has to take part.
So, for forming 47gm H2O (4÷36)×47 gm H2 has to take part
I.e. 5.22 gm of H2 has to take part
So, ans is 5.22 gm of hydrogen.
Hope it helps!!!
Uses of isotopes:
In agriculture,
C-14 is used to trace the path of photosynthesis.
In medicine,
Iodine -131 is used in the treatment of
goiter
I’d say for the answer 13.13 mmHg?
<u>Answer:</u> The true statement is iron can reduce
to gold metal
<u>Explanation:</u>
Single displacement reaction is defined as the reaction in which more reactive element displaces a less reactive element from its chemical reaction.
The reactivity of metal is determined by a series known as reactivity series. The metals lying above in the series are more reactive than the metals which lie below in the series.

Metal A is more reactive than metal B.
We are given:
Iron can reduce copper, silver can reduce gold, sodium can reduce iron and copper can reduce silver metal.
The increasing order of reactivity thus follows:

where, sodium is most reactive and gold is least reactive
For the given options:
<u>Option 1:</u> Copper cannot easily reduce sodium ion to sodium metal because it is less reactive.

<u>Option 2:</u> Iron cant easily reduce gold ion to gold metal because it is more reactive.

<u>Option 3:</u> Silver cannot easily reduce iron ion to iron metal because it is less reactive.

Hence, the true statement is iron can reduce
to gold metal