Answer:
H₂(g) + F₂(g) ⇒ 2 HF(g) ΔH°rxn = -542 kJ
Explanation:
Let's consider the unbalanced equation that occcurs when H₂(g) reacts with F₂(g) to form HF(g).
H₂(g) + F₂(g) ⇒ HF(g)
In order to get the balanced equation, we will multiply HF(g) by 2.
H₂(g) + F₂(g) ⇒ 2 HF(g)
To convert a balanced equation into a thermochemical equation, we need to add the standard enthaply of the reaction, considering that 542 kJ of energy are evolved for each mole of H₂(g) and there is 1 mole of H₂(g) in the balanced equation. By convention, when energy is released, it takes a negative sign. The thermochemical equation is:
H₂(g) + F₂(g) ⇒ 2 HF(g) ΔH°rxn = -542 kJ
Answer : The density of iron is, 7.8 g/mL
Explanation : Given,
Mass of iron = 4.7 g
Volume of water = 27.10 mL
Volume of water and iron = 27.70 mL
First we have to calculate the volume of iron.
Volume of iron = Volume of water and iron - Volume of water
Volume of iron = 27.70 mL - 27.10 mL
Volume of iron = 0.6 mL
Now we have to calculate the density of iron.
Now put all the given values in this expression, we get:
Thus, the density of iron is, 7.8 g/mL
Answer:
Ionic bonds result from the mutual attraction between oppositely charged ions. They tend to be stronger than covalent bonds due to the coulombic attraction between ions of opposite charges.
Explanation:
The reaction is
2H₂(g) + O₂(g) ---> 2H₂O
Thus as per balanced equation two moles of hydrogen will react with one moles of oxygen.
There is a directly relation between moles and volume. [One mole of each gas occupies 22.4 L of volume at STP]
Thus we can say that two unit volume of hydrogen will react with one unit volume of oxygen
Now as we have started with equal units of volume of both oxygen and hydrogen, half of oxygen will be consumed against complete volume of hydrogen
so the gas which will remain in excess is oxygen
