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3 years ago

11

Copper occurs in nature in the form of two isotopes, Cu-63 and Cu-65. Its correctly recorded atomic mass (weighted average) is 6

3.5 amu. Without doing the math, explain why it is safe to say that Cu-63 is more abundant than Cu-65.

1 answer:

OlgaM077 [116]3 years ago

6 0

63.5 is closer to 63 than 65 so you know when they find the average mass there are more Cu-63 isotopes

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Explanation: To study the outcomes, we will apply Le-Chatelier's principle.

Le-Chatelier's principle states that if there is any disturbance in the conditions of the dynamic equilibrium, the position of equilibrium will counteract the change.

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This will happen when we add the reactant to a chemical reaction. According to Le-Chatelier's principle, by increasing the reactant, the equilibrium will shift in the direction where this effect is minimal. Hence, forward reaction is favored.

2) The rate of the revere reaction increases.

This will happen when we remove the reactant from a chemical reaction. According to Le-Chatelier's principle, by removing the reactant, the equilibrium will shift in the direction where this effect is minimal. Hence, reverse reaction is favored.

3) The concentration of product increases.

This will happen when we add reactants to a chemical reaction. According to Le-Chatelier's principle, when we increase the concentration of reactants, the equilibrium will shift in the direction where this effect is minimal. Hence, the reaction will be in the forward direction which means that the concentration of product will increase.

4) The concentration of products decreases.

This will happen when we remove reactants from a chemical reaction. According to Le-Chatelier's principle, when we decrease the concentration of reactants, the equilibrium will shift in the direction where this effect is minimal. Hence, the reaction will be in the reverse direction which means that the concentration of reactants will increase or concentration of products will decrease.

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3 years ago

How many moles of zinc, Zn, are in 1.31×1024 Zn atoms?

liubo4ka [24]

Answer:

=7.89013× 10^47 moles of zinc

Explanation:

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2 years ago

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vfiekz [6]

Using the ideal gas equation:
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Substituting n with mass / Mr
PV = mRT/Mr

Density = m/V
So rearranging:
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Density = (1 x 80.6) / (0.082 x 273)
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3 years ago

Thorium-234 has a half-life of 24.1 days. How many grams of a 150 g sample would you have after 120.5 days?

chubhunter [2.5K]

Answer:

8.625 grams of a 150 g sample of Thorium-234 would be left after 120.5 days

Explanation:

The nuclear half life represents the time taken for the initial amount of sample to reduce into half of its mass.

We have given that the half life of thorium-234 is 24.1 days. Then it takes 24.1 days for a Thorium-234 sample to reduced to half of its initial amount.

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So now we start with 150 grams of Thorium-234

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In simpler way , we can use the below formula to find the sample left

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Where

$A_0$ is the initial sample amount

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3 years ago