Answer:
The percent abundance of oxygen-18 is 1.9066%.
Explanation:
The average atomic mass of oxygen is given by:
Where:
m: is the atomic mass
%: is the percent abundance
Since the sum of the percent abundance of oxygen isotopes must be equal to 1, we have:
Hence, the percent abundance of O-18 is:
Hence, the percent abundance of oxygen-18 is:
Therefore, the percent abundance of oxygen-18 is 1.9066%.
I hope it helps you!
Hi there! Relative order is an advanced order type and a absolute date is the process of determing a age.
Answer: False
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
Example: 
has similar molecular formula and empirical formula as the elements are already present in simplest of the ratios.
has molecular formula of but 
as the empirical formula.
The answer is: " 56 g CaCl₂ " .
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Explanation:
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2.0 M CaCl₂ = 2.0 mol CaCl₂ / L ;
Since: "M" = "Molarity" (measurement of concentration);
= moles of solute per L {"Liter"} of solution.
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Note the exact conversion: 1000 mL = 1 L .
Given: 250 mL ;
250 mL = ? L ? ;
250 mL * (1 L / 1000 L) = (250/1000) L = 0.25 L .
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(2.0 mol CaCl₂ / L ) * (0.25L) = (2.0) * (0.25) mol = 0.50 mol CaCl₂ ;
We have: 0.50 mol CaCl₂ ; Convert to "g" (grams):
→ 0.50 mol CaCl₂ .
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1 mol CaCl₂ = ? g ?
From the Periodic Table of Elements:
1 mol Ca = 40.08 g
1 mol Cl = <span>35.45 g .
</span>
There are 2 atoms of Cl in " CaCl₂ " ;
→ Note the subscript, "2", in the " Cl₂ " ;
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So, to calculate the molar mass of "CaCl₂" :
40.08 g + 2(35.45 g) =
40.08 g + 70.90 g = 110.98 g ; round to 4 significant figures;
→ round to 111 g/mol .
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So:
→ 0.50 mol CaCl₂ = ? g CaCl₂ ? ;
→ 0.50 mol CaCl₂ * (111 g CaCl₂ / mol CaCl₂) ;
= (0.50) * (111 g) CaCl₂ ;
= 55.5 g CaCl₂ ;
→ round to 2 significant figures;
→ 56 g CaCl₂ .
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The answer is: " 56 g CaCl₂ " .
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Los electrolitos son sustancias que se disocian en agua para dar iones.
Generalmente en química, podemos clasificar sustancias como
Los electrolitos pueden disociarse en solución para producir iones, pero un no electrolito no puede hacer eso.
Entre los electrolitos hay dos clases;
Los electrolitos fuertes se disocian completamente en solución, mientras que los electrolitos débiles no se disocian completamente en solución.
El hecho de que los electrolitos débiles no se disocien por completo significa que algunas moléculas de la sustancia no se disocian.
Por lo tanto, si los ácidos nitroso y fluorhídrico se describen como electrolitos débiles, esto significa que hay moléculas en la solución que no están disociadas.
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