Answer:
2.318032g
Explanation:
-The electrolysis equation of water is written as below:

-The mole ratio of Water to the hydrogen formed is 1:1, therefore 2.3 moles of hydrogen gas is produced.
-Hydrogen's molar mass is 1.00784 grams:

Hence, 2.318032 grams of hydrogen is produced.
Answer:
17.934 kg of water
Explanation:
If balanced equation is not given; this format can come in handy.
For any alkane of the type : CₙH₂ₙ₊₂ , it's combustion reaction will follow:
2CₙH₂ₙ₊₂ + (3n+1) O₂ → (2n)CO₂ + 2(n+1) H₂O
For butane:
2C₄H₁₀(g) + 13O₂(g) → 8CO₂(g) + 10H₂O(l)
2 moles of butane gives 10 moles of water.
1 mol of any substance has Avogadro number(N) of molecules in it( 6.022 x 10²³)
Mass of 1 mole of any substance is equal to it's molar mass
So, if 2 x N molecules of butane gives 10 x 18 g of water.
Then 1.2 x 10²⁶ molecules will give:

= 17.934 x 10³ g of water
= 17.934 kg of water
Answer:
-75 cm^3/min
Explanation:
Given from Boyle's law;
PV=C
From product rule;
VdP/dt + PdV/dt = dC/dt
but dC/dt = 0, V= 500 cm^3, P= 200kPa, dP= 30kPa/min
PdV/dt = dC/dt - VdP/dt
dV/dt = dC/dt - VdP/dt/ P
substituting values;
dV/dt = 0 - (500 * 30)/200
dV/dt = -75 cm^3/min
The question is cut off in the picture