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2 years ago

6. The half life for uranium-235 is 7.0x108 years.

Chemistry

1 answer:

kaheart [24]2 years ago

4 0

Answer:

$\large \boxed{4.0}$

Explanation:

$\text{No. of half-lives} = 2.8 \times 10^{9 } \text{ yr} \times \dfrac{\text{1 half-life}}{7.0 \times 10^{8} \text{ yr}} = \textbf{4.0 half-lives}\\\\\text{The sample went through $\large \boxed{\textbf{4.0 half-lives}}$}$

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The absorbance of a garbanzo bean solution that had been diluted by a factor of three was 0.528. what was the concentration of t

Serjik [45]

The Beer-Lambert law states that A = E*c*l where A is absorbance, E is the molar absorbance coeffecient, c is concentration and l is path length. Therefore the absorbance is directly proportional to concentration, and by increasing the concentration by a factor of 3, absorbance will increase by a factor of 3 giving A = 1.584

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2 years ago

a 0.5678 of KHP required 26.64cm³ of NaOH to complete neutralization.calculate the molarity of the NaOH solution

vladimir2022 [97]

Answer:

Explanation:

0.5678 G X GRAMS

KHC8H4O4 + NaOH = NaKC8H4O4 + H2O

1 MOL 1 MOL

0.5678G X 204G/MOL = 0.00278 MOL KHC8H4O4

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0.00278 MOL NaOH/26.26ml=0.106 molar

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1 year ago

Write a chemical equation showing how this is an acid according to the arrhenius definition. express your answer as a balanced c

Alik [6]

According to Arrhenius theory, acid is a substance that releases H⁺ ions when dissolved in water.

In order to apply this theory, the substance must be soluble in water.

H₂SO₄ is highly soluble in water. It undergoes following dissociation reaction when dissolved in water.

$H_{2}SO_{4}(aq)\overset{H_{2}O}{\rightarrow} 2H^{+}(aq)+ SO_{4}^{2-}(aq)$

From the above equation, we can see that H₂SO₄ forms 2 H⁺ ions when dissolved in water. Therefore it behaves as an acid according to Arrhenius theory.

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1 year ago

A group of students measured the average monthly temperature of 1000 cities around the world and plotted the cumulative frequenc

mr Goodwill [35]

Answer:

The MAD of city 2 is less than the MAD for city 1, which means the average monthly temperature of city 2 vary less than the average monthly temperatures for City 1.

Explanation:

For comparing the mean absolute deviations of both data sets we have to calculate the mean absolute deviation for both data sets first,

So for city 1:

Now to calculate the mean deviations mean will be subtracted from each data value. (Note: The minus sign is ignored as the deviation is the distance of value from the mean and it cannot be negative. For this purpose absolute is used)

The deviations will be added then.

So the mean absolute deviation for city 1 is 24 ..

For city 2:

Now to calculate the mean deviations mean will be subtracted from each data value. (Note: The minus sign is ignored)

The deviations will be added then.

So the MAD for city 2 is 11.33 ..

So,

The MAD of city 2 is less than the MAD for city 1, which means the average monthly temperature of city 2 vary less than the average monthly temperatures for City 1.

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1 year ago

Why does silver iodide have a higher melting point than vanillin

MAVERICK [17]

AgI has a higher melting point than vanillin because it is an ionic compound. The bonds are held more tightly together than in vanillin because it is a covalent compound. Ionic bonds have a higher melting point because the electrons are being transferred from one atom to the other.

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2 years ago