WGU D425 Exam 2026 | WGU D425 Objective
Assessment | Introduction to Chemistry |
Actual Exam Questions and Correct Answers |
Updated Version
What does a neutral atom with an atomic number greater than two
consist of? ---------CORRECT ANSWER-----------------protons, neutrons,
and electrons
Given the periodic table what is the relationship btwn electron
negativity and atomic number for halogen group 17 ---------CORRECT
ANSWER-----------------Electronegativity decreases from top to bottom
Given the periodic table what is the relationship btwn the atomic radius
and atomic number for the period 6 elements ---------CORRECT
ANSWER-----------------atomic size gradually decreases from left to right
across a period
How many valence electrons are in sulfur (S) ---------CORRECT ANSWER-
----------------6. elements in group 16 have 6 valence electrons
,Sodium has 11 electrons. which shell would contain the valence
electrons of sodium (Na) ---------CORRECT ANSWER-----------------3rd
shell. 1st shell holds 2 electrons(duet). next shell holds 8
electrons(duet). 3rd shell will hold the single valence electron
What is the definition of an ion ---------CORRECT ANSWER-----------------at
atom or a group of atoms that carries an electrical charge
How many electrons are present in a double bond ---------CORRECT
ANSWER-----------------4. double bond contains 2 bonds. each bond has 2
electrons
Which of these compounds is most likely to contain an ionic bond
N2O, NaF, H2O, C6H6 ---------CORRECT ANSWER-----------------NaF. an
ionic compound. bond btwn a metal(Na) and nonmetal(F)
Calculate the charge of iron ion in FeCl2.
there are 2 chloride anions each with -1 charge, making a total of -2(2*-
1). so the charge on the single cat ion has to be +2 to balance the
negative charge.
,Answer: ---------CORRECT ANSWER-----------------Fe+2
Calculate the charge on an iron ion Fe2O3.
there are 3 oxygen anions . Each with a -2 charge, making -6(3X-2=-6)
so the total charge on 2 iron atoms should be +6 i.e. the charge on each
iron atom is +3(+6/2=+3).
Answer: ---------CORRECT ANSWER-----------------Fe+3
Convert 12.5g in to kilograms. enter answer in kg ---------CORRECT
ANSWER-----------------0.0125
Dimensional Analysis Ex.
how many centimeters are there in 3.55m
quantity given: 3.55m
3.55m * (100cm/1m)= ---------CORRECT ANSWER-----------------
3.55m=355cm
Density converted between mass and volume of a substance
30.2ml sample of ethyl alcohol with a mass of 23.71002g
, p=23.71002g/30.2ml=0.7851
p= ---------CORRECT ANSWER-----------------p=0.785g/ml
Find mass of and object. density of alcohol is 0.7892g/mL, so alcohol is
0.7892g per 1ml. determine the mass of alcohol for 2.0mL use
2.0mL*(0.7892g/1mL)= ---------CORRECT ANSWER-----------------
1.5784g=1.5g
Density = mass/__________ ---------CORRECT ANSWER-----------------
volume
Density of an object?
mass of 2.4019 and volume of 1.40mL
2.4019g/1.40mL= ---------CORRECT ANSWER-----------------density =
1.7156g/mL= 1.72g/ml
Density of an object?
volume of 32mL and a mass of 12.24g
Assessment | Introduction to Chemistry |
Actual Exam Questions and Correct Answers |
Updated Version
What does a neutral atom with an atomic number greater than two
consist of? ---------CORRECT ANSWER-----------------protons, neutrons,
and electrons
Given the periodic table what is the relationship btwn electron
negativity and atomic number for halogen group 17 ---------CORRECT
ANSWER-----------------Electronegativity decreases from top to bottom
Given the periodic table what is the relationship btwn the atomic radius
and atomic number for the period 6 elements ---------CORRECT
ANSWER-----------------atomic size gradually decreases from left to right
across a period
How many valence electrons are in sulfur (S) ---------CORRECT ANSWER-
----------------6. elements in group 16 have 6 valence electrons
,Sodium has 11 electrons. which shell would contain the valence
electrons of sodium (Na) ---------CORRECT ANSWER-----------------3rd
shell. 1st shell holds 2 electrons(duet). next shell holds 8
electrons(duet). 3rd shell will hold the single valence electron
What is the definition of an ion ---------CORRECT ANSWER-----------------at
atom or a group of atoms that carries an electrical charge
How many electrons are present in a double bond ---------CORRECT
ANSWER-----------------4. double bond contains 2 bonds. each bond has 2
electrons
Which of these compounds is most likely to contain an ionic bond
N2O, NaF, H2O, C6H6 ---------CORRECT ANSWER-----------------NaF. an
ionic compound. bond btwn a metal(Na) and nonmetal(F)
Calculate the charge of iron ion in FeCl2.
there are 2 chloride anions each with -1 charge, making a total of -2(2*-
1). so the charge on the single cat ion has to be +2 to balance the
negative charge.
,Answer: ---------CORRECT ANSWER-----------------Fe+2
Calculate the charge on an iron ion Fe2O3.
there are 3 oxygen anions . Each with a -2 charge, making -6(3X-2=-6)
so the total charge on 2 iron atoms should be +6 i.e. the charge on each
iron atom is +3(+6/2=+3).
Answer: ---------CORRECT ANSWER-----------------Fe+3
Convert 12.5g in to kilograms. enter answer in kg ---------CORRECT
ANSWER-----------------0.0125
Dimensional Analysis Ex.
how many centimeters are there in 3.55m
quantity given: 3.55m
3.55m * (100cm/1m)= ---------CORRECT ANSWER-----------------
3.55m=355cm
Density converted between mass and volume of a substance
30.2ml sample of ethyl alcohol with a mass of 23.71002g
, p=23.71002g/30.2ml=0.7851
p= ---------CORRECT ANSWER-----------------p=0.785g/ml
Find mass of and object. density of alcohol is 0.7892g/mL, so alcohol is
0.7892g per 1ml. determine the mass of alcohol for 2.0mL use
2.0mL*(0.7892g/1mL)= ---------CORRECT ANSWER-----------------
1.5784g=1.5g
Density = mass/__________ ---------CORRECT ANSWER-----------------
volume
Density of an object?
mass of 2.4019 and volume of 1.40mL
2.4019g/1.40mL= ---------CORRECT ANSWER-----------------density =
1.7156g/mL= 1.72g/ml
Density of an object?
volume of 32mL and a mass of 12.24g
