Answer:
ΔrxnH = -580.5 kJ
Explanation:
To solve this question we are going to help ourselves with Hess´s law.
Basically the strategy here is to work in an algebraic way with the three first reactions so as to reprduce the desired equation when we add them together, paying particular attention to place the reactants and products in the order that they are in the desired equation.
Notice that in the 3rd reaction we have 2 mol Na₂O (s) which is a reactant but with a coefficient of one, so we will multiply this equation by 1/2-
The 2nd equation has Na₂SO₄ as a reactant and it is a product in our required equation, therefore we will reverse the 2nd . Note the coefficient is 1 so we do not need to multiply.
This leads to the first equation and since we need to cancel 2 NaOH, we will nedd to multiply by 2 the first one.
Taking 1/2 eq 3 + (-) eq 2 + 2 eq 1 should do it.
Na₂O (s) + H₂ (g) ⇒ 2 Na (s) + H₂O(l) ΔrxnHº = 259 / 2 kJ 1/2 eq3
+ 2NaOH(s) + SO₃(g) ⇒ Na₂SO₄ (s) + H₂O (l) ΔrxnHº = -418 kJ - eq 2
+ 2Na (s) + 2 H₂O (l) ⇒ 2 NaOH (s) + H₂ (g) ΔrxnHº = -146 x 2 2 eq 1
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Na₂O (s) + SO₃ (g) ⇒ Na₂SO₄ (s) ΔrxnHº = 259/2 + (-418) + (-146) x 2 kJ
ΔrxnH = -580.5 kJ
Covalent compounds are generally not very hard because they are formed by two or more nonmetallic atoms.
<h3>COVALENT COMPOUNDS:</h3>
Covalent compounds are compounds whose constituent elements are joined together by covalent bonds.
Covalent bonding occurs when two or more nonmetallic atoms of an element share valence electrons. This means that covalent compounds will not be physically hard since they constitute non-metals.
Examples of covalent compounds are:
- H2 - hydrogen
- H2O - water
- HCl - hydrogen chloride
- CH4 - methane
Learn more about covalent compounds at: brainly.com/question/21505413
False... Honey is greater in velosity then water
Answer:
4.52 x 10¹⁴ cycles/s
Explanation:
From c = f·λ => f = c/λ = (3.0 x 10⁸ m/s)/(6.63 x 10⁻⁷m) = 4.52 x 10¹⁴ cycles/s.
f = frequency = ?
λ = wavelength = 6.63 x 10⁻⁷ meter
c = speed of light in vacuum = 3.0 x 10⁸ meters/s
Answer:
temperature
Explanation:
Celsius is a unit of temperature. Another example of this would be Kelvin or Fahrenheit.