Assume 1mol of Al2O3:
mm(Al) = 26.98g/mol
x2(moles needed in 1mol of Al2O3)
= 53.96g
~54g
mm(O) = 16.00g/mol
x3(moles needed in 1mol of Al2O3)
=48g
mm(Al2O3) = m(Al) + m(O)
= 102g/mol
x1mol
=102g (in 1 mol)
<em>What</em><em> </em><em>percent</em><em> </em><em>of</em><em> </em><em>the</em><em> </em><em>total</em><em> </em><em>does</em><em> </em><em>X</em><em> </em><em>or</em><em> </em><em>Y</em><em> </em><em>take</em><em> </em><em>up</em><em>?</em>
Just take the portion that it gets and divide by the total:
Al: 54/102 = 53%
O: 48/102 = 47% or 100%-53%=47%
<em>Notice that, with binary compounds, you only need to calculate one of the two elements: the remaining amount HAS to be taken up by the other element, or else there would be something else involved.</em>
Answer:
Double replacement or double decomposition
Explanation:
In the reaction below, a double replacement or double decomposition has occurred.
2Na₃PO₄ + 3CaCl₂ → 6NaCl + Ca₃(PO₄)₂
This reaction occurs mainly between two ionic substances.
The reaction involves an actual exchange of partners to form new compounds. For example;
AB + CD → AD + CB
One of the following conditions below serves as the driving force for double replacement reactions:
- Formation of an insoluble compound or precipitate.
- Formation of water or any other non-ionizing compound
- Liberation of a gaseous product.
<span>zinc, nitrate and silver.
Hope this helps.
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Explanation:
To show - from E=mc²=hv show that wavelength=h/mv
Proof -
Given that,
E = mc²
E = hν
By equating both the equations, we get
mc² = hν
Because real particles do not travel at the speed of light, De Broglie submitted velocity ( v ) for the speed of light ( c ).
mv² = hν
Through the equation λ , de Broglie substituted v/λ for ν and arrived at the final expression that relates wavelength and particle with speed.
mv² = hv/λ
⇒λ = hv/mv²
⇒λ = h/mv
Hence showed.
Answer:
Mass of 1 mole of copper is 63.83 g.
0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
Explanation:
Mass of 1 copper atom,m = 
Mass of 1 mole of copper :
= 
Mass of 1 mole of copper = 63.83 g
Mass of copper penny = 2.5 g
Atomic mass of copper = 63.83 g/mol
Moles of copper in 2.5 g of copper penny:
0.03916 moles of copper atoms have a mass equal to the 2.5 grams of copper penny.
