GEN CHEM WED SESSION

Energy

100

What are the 2 conversion factors for calorie to Joule? 

(1 cal= 4.184 J)

4.184 J/ 1 cal

1cal/4.184 J

200

What is kinetic and potential energy? 

Kinetic- energy of motion (i.e. working out)

Potential- based on the position of an object or by chemical composition of a substance (i.e. ball at the top of a hill)

300

What are the most commonly used energy units?

joule (J) or kilojoules (kJ) 

calories (cal) or kilocalories (kcal) 

400

The _________ the particles move, the greater or lesser the heat or thermal energy of a substance.

faster/slower

500

A sample of water absorbs 500 calories of heat. How much energy, in joules, does the water absorb?

(1 cal= 4.184 J)

2092 J

Energy & Nutrition and Heat

100

What is specific heat? 

The amount of heat (q) that raises the temperature of exactly 1g of a substance by exactly 1 degree C. 

200

If a substance has a higher specific heat, what does that mean?

High specific heat = more heat needed for a temperature change 

(low specific heat = less heat needed for a temperature change)

300

The caloric or energy value for 1g of a food is given in ________ or _________.

kilojoules (kJ), kilocalories (kcal)

400

How much energy, in kilocalories, would be provided by a serving of food containing 15 grams of protein, 12 grams of fat, and 30 grams of carbohydrates? (Carbohydrates: 4 kcal/g, Fat: 9 kcal/g, and Protein: 4 kcal/g)

288 kcal

500

What is the heat equation and what do the variables mean?

q=mc△T

q= (measured in joules or calories) total amount of heat absorbed or released

m= (measured in grams) mass of substance

c= specific heat capacity (measured in J/g°C or cal/g°C) – This is the amount of heat needed to raise the temperature of 1 gram of the substance by 1°C)

△T= Change in temperature (measured in °C) – This is the difference between the final temperature and the initial temperature of the substance. It is calculated as:

△T=△T_Final-△T_Inital

Electron configurations/orbital diagrams

100

What is the electron configuration for oxygen (O), which has an atomic number of 8? (Hint: You can do this without a periodic table!)

1s²2s²2p⁴

^{How were you able to do this without a periodic table?}

200

How many unpaired electrons are present in the ground state of a carbon (C) atom, and in which orbitals are they located? (Carbon has atomic number 6)

Electron configuration: 1s²2s²2p²

Carbon has 2 unpaired electrons in the 2p orbitals

300

Draw the orbital diagram for nitrogen (N) (atomic number 7).

↑↓ ↑↓ ↑↑↑

1s²2s²2p³

400

Explain what is different about chromium (Cr) and copper (Cu) when writing electron configurations. Why?

Chromium: [Ar]4s¹3d⁴

Copper: [Ar]4s¹3d¹⁰

Both of these elements deviate from the expected configuration due to the stability associated with fully or half-filled 3d subshells.

500

Consider the element with the electron configuration: [Kr]5s²4d¹⁰5p⁵

Determine the following:

1. The atomic number of the element.
2. The element's position in the periodic table, including its period and group.
3. The number of unpaired electrons in the element's ground state.

1. Atomic number: 53

2. Element: Iodine (I), Period 5, Group 17

3. Number of unpaired electrons: 1

Periodic table

100

What is the smallest element? The largest? 

Helium (He)

Francium (Fr)

200

What is metallic character and the trend of metallic character on the periodic table?

An element with metallic character is one that loses valence electrons easily.

Decreases: As you move from left to right across a period

Increases: As you move down a group

300

Which element is in Period 5 and Group 4A(14)?                   

                                   

    

Tin (Sn)

400

Which of the following correctly lists the elements in order of decreasing atomic size (i.e., largest to smallest size from left to right)?

A) Na > Mg > Si > P > Ar

B) Ar > P > Si > Mg > Na 

C) Mg > Na > P > Si > Ar 

D) Si > P > Ar > Na > Mg 

E) Ar > Si > P > Na > Mg

    

A) Na > Mg > Si > P > Ar                                  

    

500

Which of the following correctly lists the elements in order of decreasing ionization energy (i.e. highest to lowest ionization energy from left to right)?               

A) Br > Se > Ga > Kr > Ge 

B) Kr > Br > Se > Ge > Ga

C) Kr > Se > Br > Ga > Ge 

D) Ga > Ge > Se > Br > Kr 

E) Ga > Br > Ge > Kr > Se                  
                       

                                   

    

B) Kr > Br > Se > Ge > Ga

Other

100

A flower arrangement has 4 red roses, 6 pink carnations, and 10 white daisies in it. What percent of the flowers in the arrangement are NOT pink carnations?

                                   

    

70%

200

Which one of the following statements about subatomic particles is false and why?

A) Neutrons and protons are found in the nucleus of an atom.

B) An atom with neutral charge has equal numbers of protons and electrons.

C) Electrons contribute very little to the mass of an atom. 

D) Electrons are attracted by protons.

E) A proton has double the mass of a neutron.

                                   

    

E) A proton has double the mass of a neutron.

Protons and neutrons have the same mass (1 amu)

300

Which of the following elements is correctly labeled as a metal, metalloid, or nonmetal? (Choose all that apply)

A) Tellurium (Te) is a metalloid. 

B) Stronium (Sr) is a metal.

C) Magnesium (Mg) is a nonmetal. 

D) Bromine (Br) is a nonmetal.

E) Selenium (Se) is a metal.

                                   

    

                                   

    

A,B,D

400

What is the chemical symbol for the isotope of an element with 15 neutrons, 17 electrons, and 17 protons?

    

³²₁₇Cl

500

For the following mathematical equation, what is the value of k?

 (2k/3)=(k/3)-3                                  

    

                                   

    

k=-9