All categories

3 years ago

Select all that apply:

2 answers:

7 0

A chemist is a registered professional who is capable and skilled to carry out experiments in the laboratory which pertains largely to chemicals. The applications which a chemist can do includes A). write a formula for a paint coating, and <span>C).determine the structure of a plant for medical purposes.</span>

Wittaler [7]3 years ago

7 0

Answer: A and C

Explanation:

A chemist is a scientist who has the knowledge of chemical science. The chemists studies the composition of a chemical substance. A chemist performs experiments on these substances for identification and knowing the chemical nature. A chemist also determine the effect of chemicals on living and non-living things. The use of different chemicals is also determined by the chemist. A chemist determine the molecular formula for many chemicals.

On the basis of the above description, A and C are the correct options.

A is correct because a paint coating may consists of many chemicals. The formula of these chemicals is required to be determined by the chemists.

C is correct as the plant may exhibit many chemicals used for the synthesis of medicine. The structural formula for these chemicals is required to be determined so as to know whether they are suitable for preparation of medicine.

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Explanation:

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the equilibrium number of vacancies at 800 °C

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Let silver be represented by N

SO;

$N = \dfrac{N_A* \rho _{Ag}}{A_{Ag}}$

where ;

$N_A =$ avogadro's number = $6.023*10^{23} \ atoms/mol$

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${Q_v = - {KT} In( \dfrac{ \ N_v }{ N})$

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$Q _v =-( 8.62*10^{-5} \ eV/atom.K * 1073 \ K) \ In( \dfrac{3.6*10^{17}}{5.3 0*10^{28}})$

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