Question

Potassium reacts with water to form basic potassium hydroxide and hydrogen gas

2K + 2H²0 ==> 2KOH + H²

How much hydrogen gas will be formed by reacting 125g potassium with 65g water?​

Answer 1

Answer:

2K + 2 H2O ------- 2KOH +H2 |^

so two moles of potassium produce of one mole of hydrogen.

3×22.4÷2 is equal to 33.6 litres of hydrogen

hope it helps u...

Answer 2

Answer:

The mass of hydrogen gas formed is $3.2g$

Explanation:

Given,

The mass of potassium = $125g$

The mass of water = $65g$

The mass of hydrogen gas formed =?

As given, the reaction:

• $2K + 2H_{2}O \rightarrow 2KOH +H_{2}$

From the reaction, we can see that;

• $2moles$ of K formed = $1mole$ of $H_{2}$

Thus,

• $1mole$ of K formed = $\frac{1}{2} moles$ of $H_{2}$

Now, the molar mass of potassium = $39g/mol$

Therefore,

• Number of moles of K = $\frac{Given mass}{Molar mass}$ = $\frac{125}{39}$ = $3.20mol$

So,

• $3.20moles$ of K formed = $3.20\times\frac{1}{2} moles$ of $H_{2}$ = $1.6moles$ of $H_{2}$

Now,

• Moles of hydrogen = $1.6mol$
• The molar mass of $H_{2}$ = $2g/mol$

Therefore, the mass of $H_{2}$ = moles of hydrogen × molar mass = $1.6\times 2$ = $3.2g$.

Hence, the mass of hydrogen gas formed is $3.2g$.