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nadezda [96]
3 years ago
15

Based on table N of the reference tables what is the number of hours required for 42k (potassium -42) to undergo three half-life

periods
Chemistry
1 answer:
skelet666 [1.2K]3 years ago
3 0

The number of hours required : 37.2 hours

<h3>Further explanation</h3>

Given

⁴²K (potassium -42)

Required

The number of hours

Solution

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.  

Usually, radioactive elements have an unstable atomic nucleus.  

Based on Table N(attached), the half-life for ⁴²K is 12.4 hours, which means half of a sample of ⁴²K will decay in 12.4 hours

For three half-life periods :

\tt 3\times 12.4=37.2~hours

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6 0
2 years ago
Which of the following weak interactions would require the least amount of energy to disrupt? Group of answer choices
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Explanation:

A hydrogen bond is defined as a weak bond that is formed between an electropositive atom (generally hydrogen atom) and an electronegative atom like oxygen, nitrogen and fluorine.

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Vander waal forces are defined as the weak electric forces which tend to attract neutral molecules towards each other in gases, liquefied and solidified gases.

Vander waal forces are very weak forces.

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8 0
3 years ago
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Answer:

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3 years ago
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Answer:

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Based on gas law, it is possible to find the ΔH of a reaction using ΔH of half reactions.

Using the reactions:

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<em>(4) </em>C(graphite) + 2H₂(g) → CH₄(g) ΔH° = -74.81 kJ

<em>(5) </em>CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(l) ΔH° = -890.3 kJ

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Now, this reaction - 4×(1) gives:

4CO(g) + 8H₂(g) → CO₂(g) + 2H₂O(l) + 3CH₄(g)

ΔH° = -1189.54kJ - 4×-110.5 = <em>-747.54kJ</em>

<em></em>

Thus <em>ΔH° of the reaction is -747.54kJ</em>

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3 years ago
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Answer: 37.0 °C , 42.5 °C

Explanation:

3 0
3 years ago
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