Moles = weight in grams / molecular weight.
So I would divide the "grams of barium" by its molecular weight (which is 137.3) to get "moles of barium". :)
<span>A 18 M solution of an acid that ionizes only slightly in solution would be termed
concentrated and weak. The concentration of the acid is high. The acid which dissociates partially in water is a weak acid.
</span><span>Calculate the [H^+] for the aqueous solution in which [OH^-] is 1 x10^-9. Is this solution acidic, basic or neutral. To determine [H+] use:
1x10^-14 = [OH-][H+]
solve for [H+]
[H+] = 1x10^-14/1x10^-9
= 1x10^-5</span>
Answer:
A mixture is created when two or more different substances are physically combined and can be separated back into its original substances. A chemical reaction occurs when two or more substances are combined to form a new substance and cannot be separated back into its original substances.
Explanation:
Answer:
20.95 g of caffeine, C₈H₁₀N₄O₂
Explanation:
From the question given above, the following data were obtained:
Number of molecules of C₈H₁₀N₄O₂ = 6.5×10²² molecules
Mass of C₈H₁₀N₄O₂ =?
From Avogadro's hypothesis,
1 mole of C₈H₁₀N₄O₂ = 6.02×10²³ molecules
Next, we shall determine the mass of 1 mole of C₈H₁₀N₄O₂. This can be obtained as follow:
1 mole of C₈H₁₀N₄O₂ = (8×12) + (10×1) + (4×14) + (2×16)
= 96 + 10 + 56 + 32
1 mole of C₈H₁₀N₄O₂ = 194 g
Thus,
194 g of C₈H₁₀N₄O₂ = 6.02×10²³ molecules
Finally, we shall determine the mass of caffeine, C₈H₁₀N₄O₂ that contains 6.5×10²² molecules. This can be obtained as follow:
6.02×10²³ molecules = 194 g of C₈H₁₀N₄O₂
Therefore,
6.5×10²² molecules = (6.5×10²² × 194) / 6.02×10²³
6.5×10²² molecules = 20.95 g of C₈H₁₀N₄O₂.
Therefore, 20.95 g of caffeine, C₈H₁₀N₄O₂ contains 6.5×10²² molecules
