Q: A sample of chlorine gas contains 75.77% $$^{35}Cl ($$atomic mass = 34.969 amu) and 24.23% $$^{37}Cl ($$atomic mass = 36.966 amu). What is the atomic weight of chlorine?

$$(0.7577 \times 34.969) + (0.2423 \times 36.966) = 35.45$$ amu

Question 1

Which of the following statements best describes the Law of Multiple Proportions?

Accepted Answer

If two elements form more than one compound, the masses of one element that combine with a fixed mass of the other are in the ratio of small whole numbers.

Question 2

Which experiment led to the discovery of the electron?

Accepted Answer

Cathode ray tube experiment

Question 3

What is the significance of the Millikan oil-drop experiment?

Accepted Answer

It determined the charge of the electron.

Question 4

Which of the following is NOT a postulate of Dalton’s atomic theory?

Accepted Answer

Atoms are indivisible and cannot be broken down further.

Question 5

Which subatomic particle has a relative mass close to zero?

Accepted Answer

Electron

Question 6

A neutral atom of chlorine has an atomic number of 17 and a mass number of 35. How many neutrons does it contain?

Accepted Answer

$$35 - 17 = 18$$ neutrons

Question 7

Which of the following elements is a metalloid?

Accepted Answer

Silicon

Question 8

Which of the following is the correct empirical formula for glucose ($$C_6H_{12}O_6$)?

Accepted Answer

$$CH_2O$$

Question 9

Which of the following is a diatomic molecule found naturally in the atmosphere?

Accepted Answer

Nitrogen ($$N_2)$$

Question 10

What is the correct name for $$FeCl_3$$?

Accepted Answer

Iron(III) chloride

Question 11

Which of the following best describes why ionic compounds are electrically neutral?

Accepted Answer

The charges of the cations and anions balance each other.

Question 12

Which of the following is the correct formula for ammonium sulfate?

Accepted Answer

$$(NH_4$)_2SO_4$$

Question 13

Which acid is correctly named according to the rules of inorganic acid nomenclature?

Accepted Answer

$$HNO_2 is $$nitrous acid

Question 14

A sample of chlorine gas contains 75.77% $$^{35}Cl ($$atomic mass = 34.969 amu) and 24.23% $$^{37}Cl ($$atomic mass = 36.966 amu). What is the atomic weight of chlorine?

Accepted Answer

$$(0.7577 	imes 34.969) + (0.2423 	imes 36.966) = 35.45$$ amu

Question 15

Which of the following is a correct statement about isotopes?

Accepted Answer

Isotopes of an element have the same number of protons but different numbers of neutrons.

Question 16

Which of the following is the correct name for $$N_2O_5$$?

Accepted Answer

Dinitrogen pentoxide

Question 17

Which of the following is a property of metals?

Accepted Answer

Shiny luster

Question 18

Which of the following is the correct formula for calcium phosphate?

Accepted Answer

$$Ca_3$$($$PO_4)_2$

Question 19

Which of the following is the correct name for $$K_2SO_4$$?

Accepted Answer

Potassium sulfate

Question 20

Which of the following best explains why the gold foil experiment disproved the 'plum pudding' model of the atom?

Accepted Answer

Most alpha particles passed through the foil, but some were deflected at large angles, indicating a dense, positive nucleus.

Atoms, Molecules, and Ions: Foundations of Modern Chemistry

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