Highlander Help

ACS I

Resources:

Have you found videos, websites, or explanations that helped you understand this chapter? Let us know and we'll add them to "Resources" part of this page for other students to use.


 

Question 1

How many atoms are in 1.75 g of Na?

Correct

 

Explanation

1.75 g Na/ (22.9898 g/ mol Na)  * (6.022*10^23)

= 4.6 * 10^22 atoms

 

Question 2

The element X occurs naturally to the extent of 65.52% 30X and the rest 32X. What is the atomic mass of X? (Use 4 sig. fig.)

Correct

 

Explanation

30(.6552)+32(1-.6652) = 30.69

 

Question 3

Select one:
 Correct

 

Explantion

  mass number - protons = neutrons

80-35=45

 

Question 4

What is the expected empirical formula of gallium oxide?

Select one:
 Correct

 

Explanation
 

 O= 2-

Ga= 3+ 


Ga2O3

 

Question 5

Which ion does not have 18 electrons?

Select one:
 Correct

 

Explanation

Sc 3+:   21e -3e = 18e

Mn5+: 25e -5e = 20e

K+: 19e-1e= 18e

P3-: 15e+3e=18e

one of these things is not like the other

 

Question 6

What is the maximum number of electrons that can occupy a px orbital?

Select one:
 Correct

 

Explanation

The maximum number of electrons that can inhabit any orbital is 2

 

Question 7

What is the valence electron configuration of the element in Period 4, Group 4A?

Select one:
 Correct

 

Explanation


Period 4 

Titanium

....4s24p2

 

Question 8

Four of the five d orbitals could be represented by

Select one:
 Correct

 

    

    

 

Question 9

What is the electron configuration of Mn5+ in the ground state?

Select one:
 Correct

 

Explanation

Regular electron configuration on Mn

 4s2


(REMEBER TO TAKE AWAY FROM THE S LEVEL FIRST)


Electron configuration Mn5+

 

 

Question 10

Which electron configuration is impossible? (Careful, excited states are possible.)

Select one:
 Correct

 

    

    

 

Question 11

How many unpaired electrons does Co2+ have?

Select one:
 Correct

 

Explanation

       

 

Question 12

Which of these species is paramagnetic?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 13

Which of these diagrams could represent the ground state of the d valence electrons of V?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 14

Which set of quantum numbers is correct and consistent with n = 3? (l = angular momentum quantum number, m= magnetic q.n., and ms = electron spin q.n.)

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 15

How many sigma bonds and pi bonds are in this structure?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 16

Arrange the nitrogen-nitrogen bond lengths in order from shortest to longest for N2, N2H2, N2H4.

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 17

An ionic substance typically exhibits all of the following properties except

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 18

The Lewis structure for Sulfur dioxide can be described by two resonance structures: 

These resonance structures indicates that the


Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 19

Which concept(s) explain why the water molecule is bent and that the angle is about 105º?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 20

Which statement is incorrect about the boiling points for the 6A hydrides: H2O, H2S, H2Se, and H2Te

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 21

Which of the following molecules is nonpolar?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 22

The molecule of the type ML4E2 consists of four single bonds and two lone pairs. What structure is it expected to assume?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 23

In which pair are the molecules geometrically similar?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 24

Which molecule is planar?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 25

What set of species is arranged in order of increasing S-N-S bond angle?

Select one:
 Correct

 

Explanation

Remember lone pairs of electrons are bulkier than bonding pairs.

 

Question 26

What type of hybrid orbital is used in PCl5?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 27

The molecule OCNH (shown below) has been detected in gas clouds between stars. The predicted O-C-N bond angle is about

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 28

MA2B2 is a molecule where M is the central atom bonded to 2 atoms of A and 2 atoms of B. The fact that it exists in only one form (no isomers) suggests its geometry is

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 29

A compound is found to consist of 28.1% sodium, 13.2% boron and 58.7% oxygen. What is its simplest formula?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 30

A compound is found to consist of 28.1% sodium, 13.2% boron and 58.7% oxygen. What is its simplest formula?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 31

A 4.000 g sample of an unknown metal, M, was completely burned in excess O2 to yield 0.02225 mol of the metal oxide, M2O3. What is the metal?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 32

What is the maximum mass in grams of aluminum chloride that could be obtained from 2.50 mol of barium chloride and excess aluminum sulfate? This is the balanced equation for the reaction: Al2(SO4)3 + 3BaCl2--> 3BaSO4 + 2AlCl3. BaCl2 molar mass is 208.3 g/mol and AlCl3molar mass is 133.3 g/mol.

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 33

1.0 x 10-5 g sample of a compound is known to contain 1.36 x 1017 molecules. This compound is

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 34

1.438 g sample of a compound of nitrogen and oxygen contains 1.000 g of oxygen. What is the empirical formula?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 35

The limiting reagent in a particular reaction can be recognized because it is the reagent that

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 36

Consider this reaction used for the production of lead. What is the maximum mass of lead that can be obtained by the reaction of 58.0 g PbO and 30.0 g ofPbS?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 37

What volume of 0.20 M BaCl2 is required to react completely with 25.0 mL of 0.600 M Na2SO4? This is the net ionic equation for the reaction:

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 38

What is the molarity of a solution made by dissolving 3.95 g of sodium acetate in water and diluting to 750. mL? (molar mass NaC2H3O2 is 82.0 g/mol.)

Correct

 

Explanation

Your content goes here...

 

Question 39

An open-ended mercury manometer is used to measure the pressure exerted by a trapped gas as shown in the figure. Atmospheric pressure is 750. mmHg. What is the pressure (in mmHg or torr) of the trapped gas if h =28 cm?

Correct

 

Explanation

Your content goes here...

 

Question 40

What volume (in mL) of 12 M HCI solution is required to prepare exactly 500. mL of a 0.55 M HCI solution?

Correct

 

Explanation

Your content goes here...

 

Question 41

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 42

A particular solid is soft, a poor conductor of heat and electricity, and has a low melting point. Generally, such a solid is classified as

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 43

The boiling point of an impure compound is generally

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 44

Given the cooling curve of one gram of a pure liquid, the length of the line BC depends on

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 45

Which phase has the largest specific heat? (Hint, how are the slope and specific heat related?)

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 46

What is the molar mass of an ideal gas if a 0.800 g sample of this gas occupies a volume of 200. mL at 50.0 oC and 720. mm Hg?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 47

What is the molar mass of an ideal gas if a 0.800 g sample of this gas occupies a volume of 200. mL at 50.0 oC and 720. mm Hg?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 48

Copper crystallizes in a face-centered cubic lattice. What is the mass of one unit cell? Report your answer in grams.

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 49

Correct

 

Explanation

Your content goes here...

 

Question 50

When a 90 g sample of an alloy at 100.0 oC is dropped into 90.0 g of water at 24.6 oC, the final temperature is 34.1 oC. What is the specific heat of the alloy? (The specific heat of water is 4.184 J/(goC).)

Correct

 

Explanation

Your content goes here...

 

Question 51

What is the enthalpy of formation of CO(g) in kJ? 2CO(g) + O2(g) --> 2CO2(g). ΔH reaction = -566 kJ ; ΔH CO2(g) =-393.5 kJ/mol.

Correct

 

Explanation

Your content goes here...

 

Question 52

Correct

 

Explanation

Your content goes here...

 

Question 53

When 137 J of energy are added to a sample of gallium that is initially at 25.0 oC, the temperature rises to 48.0 oC. What is the volume of the sample in cubic centimeter?

Correct

 

Explanation

Your content goes here...

 

Question 54

Calculate the change in enthalpy for the chemical reaction N2(g) + 3H2(g) --> 2NH3(g)

Select one:
 Correct

 

Explanation

(N triple N) -3(H-H)-2(3(N-H))

946+3(436)-6(389)

=-80

 

Question 55

The following question is from the ACS Study Guide. It would be better to ask which diagram best represents the change in enthalpy for the dissolution process.

Select one:
 Correct

 

Explanation

If the solution gets cold than it is endothermic so enthalpy should increase because an endothermic reaction should have a positive number

 

Question 56

For which of the following reaction is the enthalpy of formation of the compound equal to the ΔH of reaction?

Select one:
 Correct

 

Explanation

C(graphite) and O2 enthalpy is = 0

 so the enthalpy of formation will be the same as the enthalpy of reaction

 

Question 57

Which of these elements is predicted to be the most active nonmetal?

Select one:
 Correct

 

Explanation

X because its electronegativity value is the highest

 

Question 58

When C30H50O2 is completely oxidized with excess oxygen, what are the products?

Select one:
 Correct

 

Explanation

oxidization and combustion typically leads to H2O and CO2 as products

 

Question 59

In what part of the periodic table are the largest electronegativities found?

Select one:
 Correct

 

Explanation

Your content goes here...

 

Question 60

Which gas is LEAST soluble in water?

Select one:
 Correct

 

Explanation

The most non polar will be the least soluble

(like dissolves like)

 

Question 61

In what part of the periodic table are the smallest ionization energies for the first electron found?

Select one:
 Correct

 

Explanation

    

 

Question 62

Arrange the elements Li, Be, Ne, and Ar in increasing order of the energy required to remove an electron from their respective gaseous atoms.

Select one:
 Correct

 

    

    

 

Question 63

The first four ionization energies of an element X are 0.58, 1.82, 2.74, and 11.58 MJ/mol. What is the most likely formula for a stable ion of X?

Select one:
 Correct

 

Explanation

Count the number of ionization energies until the largest jump

 

Question 64

If the formula of an oxide of element X is XO, what is the formula of the nitride of X?

Select one:
 Correct

 

Explanation

O = 2- 

so X should equal 2+


so for a nitride in which N = 3-

X3N2 is the most appropriate

 

Question 65

When the three ions N3-, O2-, and F- are arranged in order of increasing ionic radius, which is the correct order?

Select one:
 Correct

 

Explanation

    

 

Question 66

When the three elements P, Cl, and As are arranged in order of increasing atomic radius, which is the correct order?

Select one:
 Correct

 

    

    

 

Question 67

In what part of the periodic table are the largest atoms found?

Select one:
 Correct

 

    

    

 

Question 68

Which is a characteristic property of transition elements?

Select one:
 Correct

 

    

    


Comments