Answer : The enthalpy change for the reaction is, 419.5 kJ
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
The given chemical reaction is,
Now we have to determine the enthalpy change for the reaction below:
By reversing and then dividing the reaction by 2, we get the enthalpy change for the reaction.
The expression will be:
Therefore, the enthalpy change for the reaction is, 419.5 kJ
Answer:
to collect measurable, empirical evidence in an experiment related to a hypothesis the results aiming to support or contradict a theory.
Explanation:
Calcium carbonate when mixed with water result in the
formation of Calcium hydroxide which is used as an antacid. The chloride ion
also helps in the whitening of teeth thus finding its use as an ingredient in toothpaste.
Iron oxide is dark pigment which is naturally used in
makeup.
<span>Therefore the
answer to this question is
Swap the uses for iron oxide and calcium
carbonate. </span>
<span> </span>
Answer:
<h2>Density = 0.00026 g/mL</h2>
Explanation:
The density of a substance can be found by using the formula
<h3>
</h3>
From the question
mass of air = 1.2 g
volume = 4,555 mL
Substitute the values into the above formula and solve for the density
That's
<h3>
</h3>
= 0.0002634
We have the final answer as
<h3>Density = 0.00026 g/mL</h3>
Hope this helps you
Equation is as follow,
<span> 4 Na (s) + O</span>₂ <span>(g) → 2Na</span>₂<span>O (s)
According to equation,
91.92 g (4 moles) of Na produces = 123.92 g (2 moles) of Na</span>₂O
So,
17.4 g of Na will produce = X g of Na₂O
Solving for X,
X = (17.4 g × 123.92 g) ÷ 91.92 g
X = 23.45 g of Na₂O