Question
What types of chemical reactions are the following?
Column A
1:2 H2O → 2 H2 + O2
2: 2 C2H6 + 7 O2 → 4 CO2 + 6 H2O
3: 2 Na + Cl2 → 2 NaCl
4: 4 AlBr3 + 3 O2 → 2 Al2O3 + 6 Br2
5: KCl + NaI → KI + NaCl
Column A
1:2 H2O → 2 H2 + O2
2: 2 C2H6 + 7 O2 → 4 CO2 + 6 H2O
3: 2 Na + Cl2 → 2 NaCl
4: 4 AlBr3 + 3 O2 → 2 Al2O3 + 6 Br2
5: KCl + NaI → KI + NaCl
Answers
GPT-4o mini
Let's analyze the reactions provided in Column A and identify their types:
1. **\(2 H_2O \rightarrow 2 H_2 + O_2\)**
- **Type: Decomposition Reaction**
- This reaction involves the breakdown of water into hydrogen and oxygen gas.
2. **\(2 C_2H_6 + 7 O_2 \rightarrow 4 CO_2 + 6 H_2O\)**
- **Type: Combustion Reaction**
- This is the combustion of ethane (C2H6) in the presence of oxygen, producing carbon dioxide and water.
3. **\(2 Na + Cl_2 \rightarrow 2 NaCl\)**
- **Type: Synthesis Reaction**
- This reaction involves the formation of sodium chloride from its elements sodium and chlorine.
4. **\(4 AlBr_3 + 3 O_2 \rightarrow 2 Al_2O_3 + 6 Br_2\)**
- **Type: Redox Reaction (Combination of Synthesis and Decomposition)**
- This reaction can be viewed as both a synthesis (formation of aluminum oxide) and a redox process where aluminum is oxidized and bromine is reduced.
5. **\(KCl + NaI \rightarrow KI + NaCl\)**
- **Type: Double Displacement Reaction** (or Metathesis Reaction)
- This reaction involves the exchange of ions between the two compounds, resulting in the formation of new compounds.
In summary:
1. Decomposition
2. Combustion
3. Synthesis
4. Redox (Combination of Synthesis and Decomposition)
5. Double Displacement (Metathesis)
1. **\(2 H_2O \rightarrow 2 H_2 + O_2\)**
- **Type: Decomposition Reaction**
- This reaction involves the breakdown of water into hydrogen and oxygen gas.
2. **\(2 C_2H_6 + 7 O_2 \rightarrow 4 CO_2 + 6 H_2O\)**
- **Type: Combustion Reaction**
- This is the combustion of ethane (C2H6) in the presence of oxygen, producing carbon dioxide and water.
3. **\(2 Na + Cl_2 \rightarrow 2 NaCl\)**
- **Type: Synthesis Reaction**
- This reaction involves the formation of sodium chloride from its elements sodium and chlorine.
4. **\(4 AlBr_3 + 3 O_2 \rightarrow 2 Al_2O_3 + 6 Br_2\)**
- **Type: Redox Reaction (Combination of Synthesis and Decomposition)**
- This reaction can be viewed as both a synthesis (formation of aluminum oxide) and a redox process where aluminum is oxidized and bromine is reduced.
5. **\(KCl + NaI \rightarrow KI + NaCl\)**
- **Type: Double Displacement Reaction** (or Metathesis Reaction)
- This reaction involves the exchange of ions between the two compounds, resulting in the formation of new compounds.
In summary:
1. Decomposition
2. Combustion
3. Synthesis
4. Redox (Combination of Synthesis and Decomposition)
5. Double Displacement (Metathesis)
Question 13
When an ice cube melts in your hand, it changes from a solid to a liquid.
H2O (s) → H2O (l)
This is an example of ________________ reaction, because heat is _____________ the system.
a
endothermic; leaving
b
exothermic; entering
c
endothermic; entering
d
exothermic; leaving
When an ice cube melts in your hand, it changes from a solid to a liquid.
H2O (s) → H2O (l)
This is an example of ________________ reaction, because heat is _____________ the system.
a
endothermic; leaving
b
exothermic; entering
c
endothermic; entering
d
exothermic; leaving
GPT-4o mini
The melting of an ice cube in your hand is an example of an **endothermic reaction**, because heat is **entering** the system from your hand to facilitate the phase change from solid (ice) to liquid (water).
Therefore, the correct answer is:
**c. endothermic; entering**
Therefore, the correct answer is:
**c. endothermic; entering**
Question 14
A fire is an example of ________________ reaction, because heat is _____________ the system.
a
endothermic; entering
b
endothermic; leaving
c
exothermic; entering
d
exothermic; leaving
A fire is an example of ________________ reaction, because heat is _____________ the system.
a
endothermic; entering
b
endothermic; leaving
c
exothermic; entering
d
exothermic; leaving
GPT-4o mini
A fire is an example of an **exothermic reaction** because it releases heat into the surroundings.
Therefore, the correct answer is:
**d. exothermic; leaving**
Therefore, the correct answer is:
**d. exothermic; leaving**
Question 15
The energy that is needed to start a chemical reaction is called:
a
chemical reactions do not need energy to start
b
activation energy
c
exothermic energy
d
start-up energy
The energy that is needed to start a chemical reaction is called:
a
chemical reactions do not need energy to start
b
activation energy
c
exothermic energy
d
start-up energy
GPT-4o mini
The energy that is needed to start a chemical reaction is called:
**b. activation energy**
**b. activation energy**
Question 16
Which of the following is NOT a way to speed up a chemical reaction? (Select all that apply)
a
increasing the temperature of one of the reactants
b
decreasing the surface area of one of the reactants
c
increasing the concentration of one of the reactants
d
decreasing the temperature of one of the reactants
Which of the following is NOT a way to speed up a chemical reaction? (Select all that apply)
a
increasing the temperature of one of the reactants
b
decreasing the surface area of one of the reactants
c
increasing the concentration of one of the reactants
d
decreasing the temperature of one of the reactants
GPT-4o mini
To determine which options are NOT ways to speed up a chemical reaction, let's analyze each one:
a. **Increasing the temperature of one of the reactants** - This speeds up the reaction; **not correct.**
b. **Decreasing the surface area of one of the reactants** - This slows down the reaction, as less surface area means fewer collisions between reactant molecules; **correct.**
c. **Increasing the concentration of one of the reactants** - This speeds up the reaction; **not correct.**
d. **Decreasing the temperature of one of the reactants** - This slows down the reaction because lower temperatures generally reduce the kinetic energy of molecules; **correct.**
Therefore, the correct answers are:
**b (decreasing the surface area of one of the reactants)** and **d (decreasing the temperature of one of the reactants)**.
a. **Increasing the temperature of one of the reactants** - This speeds up the reaction; **not correct.**
b. **Decreasing the surface area of one of the reactants** - This slows down the reaction, as less surface area means fewer collisions between reactant molecules; **correct.**
c. **Increasing the concentration of one of the reactants** - This speeds up the reaction; **not correct.**
d. **Decreasing the temperature of one of the reactants** - This slows down the reaction because lower temperatures generally reduce the kinetic energy of molecules; **correct.**
Therefore, the correct answers are:
**b (decreasing the surface area of one of the reactants)** and **d (decreasing the temperature of one of the reactants)**.
Match the trend on the periodic table to its description
Column A
1.
a measure of how strongly atoms attract bonding electrons to themselves
2.
the amount of energy required to remove an electron from an atom or molecule:
3.
a measure of the size of an atom:
Column B
a.electronegativity
b.ionization energy
c.atomic radius
Column A
1.
a measure of how strongly atoms attract bonding electrons to themselves
2.
the amount of energy required to remove an electron from an atom or molecule:
3.
a measure of the size of an atom:
Column B
a.electronegativity
b.ionization energy
c.atomic radius
GPT-4o mini
Here are the matches between the trends in Column A and their corresponding descriptions in Column B:
1. **a measure of how strongly atoms attract bonding electrons to themselves**
- **Match: a. electronegativity**
2. **the amount of energy required to remove an electron from an atom or molecule**
- **Match: b. ionization energy**
3. **a measure of the size of an atom**
- **Match: c. atomic radius**
So, the matches are:
1 → a
2 → b
3 → c
1. **a measure of how strongly atoms attract bonding electrons to themselves**
- **Match: a. electronegativity**
2. **the amount of energy required to remove an electron from an atom or molecule**
- **Match: b. ionization energy**
3. **a measure of the size of an atom**
- **Match: c. atomic radius**
So, the matches are:
1 → a
2 → b
3 → c