Question

Identify the element shown below.

a) Magnesium (Mg)
b) Hydrogen (H)
c) You cannot identify the element, there is not enough information.
d) Helium (He)
e) Calcium (Ca)

A student tests an unknown substance for the following properties and finds the results listed in the table below. Given this information, which of the following is the most reasonable conclusion for the student to reach?
a) The substance is a metalloid.
b) The substance is a metal.
c) The substance is a noble gas.
d) The substance is a non-metal.

Which of the statements accurately compares the elements shown in the table below?
a) Fluorine is the most reactive because it has 7 valence electrons.
b) Silicon is the most reactive because it is a metalloid.
c) Gallium is the most reactive because it has the most neutrons.
d) Boron is the most reactive because Boron has the least amount of protons.

Which of the statements below is correct?
a) Statement 1
b) Statement 2
c) Statement 3
d) Statement 4

An atom is extremely tiny, and is considered the smallest part of matter. In order to be classified as matter, an atom must have mass. What makes up most of the atom’s mass?
a) The nucleus because it contains protons and neutrons
b) The nucleus because it contains protons and electrons
c) The electron cloud because it has the most volume in the atom
d) The nucleus because it contains all three subatomic particles

Below is a partial periodic table showing the location of 6 elements. How many valence electrons will the element marked by #6 have?
a) 8
b) 6
c) 4
d) 18

Which of the following best describes an electron?
a) It has a positive charge, and much more mass than a neutron.
b) It has no charge, and about the same mass as a proton.
c) It has a negative charge, and much less mass than a proton.
d) It has a negative charge, and about the same mass as a neutron.

Which atom model below is the least reactive?
a) A
b) C
c) D
d) B

Which statement is correct about the periodic table below? Choose all that are correct.
a) Element 3 is an average conductor of electricity.
b) Element 3 has 3 more valence electrons than Element 1.
c) Element 2 has the same number of electrons as element 4.
d) Element 2 has the same number of energy levels as element 4.

Valence electrons are
a) the electrons in the outermost occupied shell of an atom. Valence electrons determine reactivity of an atom.
b) the electrons located in all of the shells added together. Valence electrons determine the mass of an atom.
c) the electrons located in the shell closest to the nucleus. Valence electrons determine reactivity of an atom.
d) the electrons located in the outermost occupied shell of an atom. Valence electrons determine the mass of the atom.

Which element has 6 energy levels and 7 valence electrons?
a) Seaborgium (Sg)
b) Rhenium (Re)
c) Astatine (At)
d) Polonium (Po)

What is the mass number of a Cesium (Cs) atom that has 78 neutrons?
a) 132.9
b) 132
c) 133
d) 55

A model of Beryllium is shown. What type of particles are found in the cloud surrounding the atom's nucleus?
a) Positively charged particles only
b) Neutral particles and positively charged particles
c) Positively and negatively charged particles
d) Negatively charged particles only

Below is a partial periodic table showing the location of 6 elements. Which would be more reactive, an element found in the same group as Element 5, or an element found in the same group as Element 6?
a) Elements in the same group as Element 5
b) Both groups are non-reactive.
c) Both groups are very reactive.
d) Elements in the same group as Element 6

A new element has been discovered, and it has been placed at the bottom of Group 1. What physical and chemical properties will this element have?
a) dull, brittle, not reactive
b) average conductor, shiny, reactive
c) shiny, malleable, reactive
d) dull, brittle, reactive

Answer 1

In the periodic table, Group 1 contains alkali metals, Group 17 houses the reactive halogens, and Group 18 consists of the unreactive noble gases. Magnesium has an atomic number of 12, and similar chemical properties are observed in elements within the same group due to the same number of valence electrons.

Step-by-step explanation:

To identify the element belonging to Group 1, we refer to elements that are known as alkali metals. These include lithium, sodium, potassium, rubidium, cesium, and francium. All group 1 elements have one electron in their outer shell, giving them similar chemical properties. The halogens are found in Group 17, and these elements, including fluorine, chlorine, bromine, iodine, and astatine, are all one electron short of a full outer shell, making them very reactive.

Noble gases occupy Group 18 on the periodic table and are characterized by having full energy orbitals, which explains their lack of reactivity. The elements that have an atomic number of 12 which is magnesium, are able to be determined based on the periodic table where each element is listed with its corresponding atomic number.

An element that contains electrons in the 4th energy level can be determined by the element's period number, which corresponds with the number of occupied electron shells. Considering elements that will have similar chemical properties, these would be elements within the same group as they share the same number of valence electrons and tend to exhibit similar chemical behaviors.