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Eddi Din [679]
3 years ago
9

A radioactive substance of mass 768g has a half life of 3 years. After how many years does it leave only 6g undecayed?​

Chemistry
2 answers:
vagabundo [1.1K]3 years ago
8 0

Answer:

The answer is 21 years.

Explanation:

7×3

sammy [17]3 years ago
5 0

Answer:

hi

good morning

myself veeresh

and you

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The dissolution of borax in water is a temperature dependent reaction. With the higher temperature, the salt dissolve quickly.

<h3>What is borax?</h3>

Borax is the hydrate salt of boric acid. It is white and widely used in cleaning and in laundry  detergent.

Borax is a salt that will dissolve in water at almost any temperature, with the exception of steam and ice.

However, as with any salt, the higher the temperature, the faster the salt dissolves, so speed is dependent on temperature. It will dissolve in cold water, but it will take longer.

Thus, the dissolution of borax in water is a temperature dependent reaction.

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Which of the following organisms evolved after amphibians?
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A pure substance has a definite chemical composition

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Metallic copper is formed when aluminum reacts with copper(ii) sulfate. how many grams of metallic copper can be obtained when 5
exis [7]
Answer is: 127 grams <span>rams of metallic copper can be obtained.
</span>Balanced chemical reaction: 2Al + 3CuSO₄ → Al₂(SO₄)₃ + 3Cu.
m(Al) = 54.0 g.
n(Al) = m(Al) ÷ M(Al).
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n(Al) = 2 mol.
m(CuSO₄) = 319 g.
n(CuSO₄) = 319 g ÷ 159.6 g/mol.
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From chemical reaction: n(CuSO₄) : n(Cu) = 3 : 3 (1 : 1).
n(Cu) = 2 mol.
n(Cu) = 2 mol · 63.55 g/mol.
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3 years ago
Questions and answers about isotopes grade 8 I need this for a PowerPoint exam projects
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Answer:

Question: A patient is diagnosed with a damage in the thyroid gland.

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