CHE 102: Chapter 3- Atoms and Elements

Which of these is the correct chemical symbol for potassium?

K

Which pair of elements do you expect to be most similar ?

O and S

Which of the following is true?

Oxygen and sulfur are in the same group

The elements of the group 7A will all form ions. These ions will be _____ and will have a charge of _____.

anions; 1−

The number of protons in a neutral atom is equal to the _____ of the atom.

atomic number

Nonmetals tend to _____ electrons to form _____ ions

gain; negative

What is the charge on an ion that contains 16 protons and 18 electrons?

−2

Determine the correct number of protons and electrons in P3−.

15 protons and 18 electrons

Chlorine has two isotopes, 35Cl and 37Cl, whose respective abundances are 75.77% and 24.23% and masses are 34.9688 amu and 36.9659 amu. Calculate the atomic mass of chlorine

35.45 amu

The correct symbol for the isotope of potassium with 22 neutrons is ________.

41 K 19

How many atoms does one mole of aluminum contain?

6.022x10^23

Which of these elements has three valence electrons?

Al

The elements Li, Na, K, Pb and Cs are the members of which group/ family?

Alkali metals

Which of these statements about atoms is incorrect?

Atoms are the smallest visible particles of an element.

Which of these is the correct chemical symbol for carbon?

C

Which of these particles has a negative charge?

Electron

Which of the following statements about electrons is incorrect?

Electrons exist in the nucleus of the atom

Which of these elements is a metal?

Mg

The most abundant element in the Earth's crust by mass is _____.

oxygen

Isotopes of an element have the same number of _____ but a different number of _____.

protons; neutrons