Module 04 : Reactions

Question 1

The reaction 2NO_(g) + O2_(g) → 2NO2_(g) is a synthesis reaction. (2 points)

True

False

Answer 1

True

Question 2

What is true of synthesis and decomposition reactions? (4 points)

1. Synthesis reactions require more energy than decomposition reactions.
2. Synthesis reactions produce more products than decomposition reactions.
3. Synthesis reactions are the opposite of decomposition reactions.
4. Synthesis reactions have fewer reactants than decomposition reactions.

Answer 2

3. Synthesis reactions are the opposite of decomposition reactions.

Question 3

A synthesis reaction can be identified because it only has pure elements on the left side of the arrow and compounds on the right side of the arrow. (2 points)

1. True
2. False

Answer 3

False

Question 4

Which chemical equation correctly represents the synthesis of calcium sulfite from calcium oxide and sulfur dioxide? (4 points)

1. CaSO_3(s) → CaO_(s) + SO^2(g)
2. CaSO_3(s) + O^2(g) → CaO_(s) + SO2_(g)
3. CaO_(s) + SO_2(g) → CaSO_3(s)
4. CaO_(s) + SO_2(g) → CaSO_3(s) + O2_(g)

Answer 4

3. CaO_(s) + SO_2(g) → CaSO_3(s)

Question 5

Which of the following is a synthesis reaction? (4 points)

1. AgNO₃ + NaCl → AgCl + NaNO₃
2. CH₄ + O₂ → CO₂ + H₂O
3. SO₃ + H₂O → H₂SO₄
4. Cu + AgNO₃ → Ag + CuNO₃

Answer 5

3. SO₃ + H₂O → H₂SO₄

Question 6

An unbalanced chemical equation is shown:

H₂O₂ → 2H₂O + O₂

Which of the following statements explains why the equation is not balanced? (4 points)

1. Two H₂O₂ molecules should decompose to form the given products.
2. Four H₂O₂ molecules should decompose to form the given products.
3. Two H₂O₂ molecules should undergo a synthesis reaction to form the given products.
4. Four H₂O₂ molecules should undergo a synthesis reaction to form the given products.

Answer 6

1. Two H₂O₂ molecules should decompose to form the given products.

Question 7

Define a Synthesis Reaction:

Answer 7

Synthesis Reaction: reaction two+ reactants combine to form one product

A + B → AB

Question 8

Define Decomposition reaction:

Answer 8

Decomposition Reaction: Single compound reactant to form more than one product

AB → A + B

Question 9

What are the components of Chemical equations?

Answer 9

A chemical reaction involves bonds being broken and formed as atoms rearrange to make new substances

Reactant: Initial substance before chemical change

Product: New substance after a chemical change

Question 10

Define Chemical Change:

Answer 10

• Left to right
• Represented in chemical formulas
• The phase of each substance indicated in subscripts
  (s) for solid, (l) for liquid, and (g) for gas
  (aq) → aqueous solution → compounds dissolved in water to forma solution

Question 11

Define the Law of Conservation of Mass:

Answer 11

Law of Conservation of Mass: Mass cannot be created or destroyed within a closed system

• In chemical equations: equal number of elements on both sides of the equation
• in experiments the initial weight/volume will be the same total at the end

Question 12

Fill in the blank with the correct number to balance the equation: 4Cr + 3O₂ → Cr₂O₃. (Enter only a whole number.) (3 points)

Answer 12

2

Question 13

For the reaction VCl₂ + Cl₂ → VCl₅, what are the reactants, products, and correct coefficients in the balanced equation? (3 points)

1. Reactants: 2VCl₂ and 3Cl2; product: 2VCl₅
2. Reactants: 2VCl₂ and 1Cl₂; product: 2VCl₅
3. Products: 1VCl₂ and 2Cl₂; reactant: 1VCl₅
4. Products: 2VCl₂ and 1Cl₂; reactant: 2VCl₅

Answer 13

1. Reactants: 2VCl₂ and 3Cl2; product: 2VCl₅

Question 14

Which of the following laboratory procedures best illustrates the law of conservation of mass? (Assume the product of the reaction includes the mass of any unused reactants.) (3 points)

1. Calculating the number of atoms in 11 g of Na
2. Using 250 g of impure Cu to obtain 200 g of pure Cu
3. Heating 32 g of S and 56 g of Fe to produce 88 g of FeS
4. Burning 2.4 g of Mg in an open crucible to produce 2 g of MgO

Answer 14

3. Heating 32 g of S and 56 g of Fe to produce 88 g of FeS

Question 15

A chemical equation is shown:

Al + O₂ → Al₂O₃

According to the law of conservation of mass, how many atoms of oxygen exist in the products of this reaction? (3 points)

1. 6
2. 5
3. 3
4. 2

Answer 15

1. 6

Question 16

When methane, CH₄, is combusted, it produces carbon dioxide, CO₂, according to the unbalanced equation: CH₄ + O₂ → CO2 + H₂O.

Write the balanced equation for this reaction, and explain how it is possible for 10 grams of methane fuel to burn and emit 27 grams of carbon dioxide. Discuss whether or not this reaction obeys the law of conservation of mass. (5 points)

Answer 16

In the equation above, there are 4 hydrogen atoms on the left side and only two on the right; therefore, a coefficient of 2 has to be added before the compound H20. Now the equation is as follows: CH₄ + O₂ → CO₂ + 2H₂O. On the right side of the equation, there are 4 oxygen atoms now and only two on the left, so a coefficient of two has to be added to the left oxygen atom to make it equal to four: CH₄ + 2O₂ → CO₂ + 2H₂O. There is 1 carbon atom on the left and the right, so the element is balanced. Since, according to the Law of Conservation of Mass, the energy/amount of atoms has to stay the same, the balanced equation is CH₄ + 2O₂ → CO₂ + 2H₂O.

All reactions have to obey the Law of Conservation of Mass, so even when the transfer of matter is not clear; therefore, the reaction above has to make logical sense in some way or another. Even though the methane in the initial reactants weighed less than the CO2, the diatomic oxygen atom also contributed to the reactants’ weight, so the carbon chemically reacted with the oxygen, which is why it weighs more in the product than the reactant.

Question 17

Define Single Replacement Reactions:

• What is the formula
• and the components of the formula

Answer 17

Reaction one element replaces a similar element in a compound

A + BC → AC + B

• A → neutral element
• BC → ionic compound
• Positive ion A replaces positive ion B in ionic compound

Question 18

Define Double Replacement Reactions:

• What is the formula
• and the components of the formula

Answer 18

Reaction in which ions of two compounds exchange places in aqueous solution to form two new compounds

AB + CD → AD + CB

• A, B, C, D → reactants represent ions

A & C: positive ions

B & D negative ions

• AD & CB → ionic or molecular compounds

Question 19

What are the reactants and products of Single Replacement Reactions?

Answer 19

Reactants: element + compound

Product: different element + different compound

Question 20

What are the reactants and products of double replacement reactions?

Answer 20

Reactants: two compounds

Product: two different compounds

products are typical:

• precipitate or solid
• gas (bubbles)
• water

Question 21

What is the “Active Series?”

Answer 21

• list elements in reactivity
• SRR: when the replacement element more reactive than the element it tries to replace

Question 22

What are:

1. Beginning Reactions
2. Ionic Breakdown
3. Balanced Equations

Answer 22

Beginning Reactions:

• positive ions of reactants switch positions to create a product

Ionic Breakdown:

• ions trade places
• combine form neutral compounds

Balanced Equations:

• coefficients used balance overall equation

Question 23

What are the observable changes in Double Reaction Equations?

Answer 23

1. Insoluble Product
2. Molecular Product
3. Predipitate

Question 24

Define Aqueous solutions:

Answer 24

the reaction only noticeable when a change is appearance or state occurs

Question 25

Define **Acid-Base Reactions:**

Answer 25

Process of neutralization of acid using a base → **Acid-Base Reaction** or **Neutralization Reaction** * double displacement reaction *

Question 26

What is a **salt**, acid-based reaction?

Answer 26

ionic compound formed by reaction of acid and base

Question 27

Define **_Acid:_**

Answer 27

**substance is hydrogen ion donor when dissolved in water/reaction** Most acids: H⁺

Question 28

Define *Base:*

Answer 28

* Substance hydrogen acceptor in the reaction * Produces hydroxide ions when dissolved in water Most Bases: **OH**

Question 29

The reaction 2NO_(g) + O_2(g) → 2NO_2(g) is a synthesis reaction. (2 points) **True or False**

Answer 29

True

Question 30

What is true of synthesis and decomposition reactions? (4 points) 1. Synthesis reactions require more energy than decomposition reactions. 2. Synthesis reactions produce more products than decomposition reactions. 3. Synthesis reactions are the opposite of decomposition reactions. 4. Synthesis reactions have fewer reactants than decomposition reactions.

Answer 30

**3.** Synthesis reactions are the opposite of decomposition reactions.

Question 31

A synthesis reaction can be identified because it only has pure elements on the left side of the arrow and compounds on the right side of the arrow. (2 points) True or False

Answer 31

False

Question 32

Which chemical equation correctly represents the synthesis of calcium sulfite from calcium oxide and sulfur dioxide? (4 points) 1. CaSO_3(s) → CaO_(s) + SO2_(g) 2. CaSO_3(s) + O_2(g) → CaO_(s) + SO_2(g) 3. CaO_(s) + SO_2(g) → CaSO_3(s) 4. CaO_(s) + SO_2(g) → CaSO_3(s) + O_2(g)

Answer 32

**3.** CaO_(s) + SO_2(g) → CaSO_3(s)

Question 33

Which of the following is a synthesis reaction? (4 points) 1. AgNO₃ + NaCl → AgCl + NaNO₃ 2. CH₄ + O₂ → CO₂ + H₂O 3. SO₃ + H₂O → H₂SO₄ 4. Cu + AgNO₃ → Ag + CuNO₃

Answer 33

**3.** SO₃ + H₂O → H₂SO₄

Question 34

An unbalanced chemical equation is shown: H₂O₂ → 2H₂O + O₂ Which of the following statements explains why the equation is not balanced? (4 points) 1. Two H₂O₂molecules should decompose to form the given products. 2. Four H₂O₂molecules should decompose to form the given products. 3. Two H₂O₂molecules should undergo a synthesis reaction to form the given products. 4. Four H₂O₂molecules should undergo a synthesis reaction to form the given products.

Answer 34

**1.** Two H₂O₂molecules should decompose to form the given products

Question 35

A single replacement reaction is a reaction in which one element replaces a similar element within a compound. (2 points) True False

Answer 35

True

Question 36

Which of the following equations has the correct products and is balanced correctly for a reaction between Na₃PO₄ and KOH? (4 points) 1. Na₃PO₄ + 3KOH → 3NaOH + K₃PO₄, because K retains the same charge throughout the reaction 2. Na₃PO₄ + 3KOH → Na₃OH + KPO4, because K increases in charge from 1+ to 3+ when it is replaced 3. Na₃PO₄+ KOH → 3NaOH + K₃PO₄, because K retains the same charge throughout the reaction 4. Na₃PO₄+ KOH → Na₃OH + K₃PO₄, because K increases in charge from 1+ to 3+ when it is replaced

Answer 36

**1.** Na₃PO₄ + 3KOH → 3NaOH + K₃PO₄, because K retains the same charge throughout the reaction

Question 37

When I₂ and FeCl₂ are mixed together, iodine (I) cannot replace chlorine (Cl) in the compound because iodine is lower on the periodic table. (2 points) True or False

Answer 37

True

Question 38

Which of the following is a double replacement reaction? (4 points) 1. Ca(OH)₂ + H₂SO₄ → CaSO₄ + 2H₂O 2. CH₄ + 2O₂ → CO₂ + 2H₂O 3. 8Fe + S₈ → 8FeS 4. Zn + H₂SO₄ → ZnSO₄ + H₂

Answer 38

**1.** Ca(OH)₂ + H₂SO₄ → CaSO₄ + 2H₂O

Question 39

A double replacement reaction is a reaction in which one element replaces a similar element within a compound. (2 points) True or False

Answer 39

False

Question 40

When HNO₃ and Au are mixed together, what do you expect to happen, and why? (4 points) 1. No reaction, because Au is above H on the activity series and they cannot react 2. No reaction, because Au is lower on the activity series and cannot replace H 3. They form Au(NO₃)₂ and H₂, because Au is more reactive and able to replace H 4. They form Au(NO₃)₂ and H₂, because they trade places in a double replacement reaction

Answer 40

**2.** No reaction, because Au is lower on the activity series and cannot replace H

Question 41

The table shows the nature of the reactants and products formed in a certain type of chemical reaction. Nature of Reactants and Products Reactants Products Ionic compound + Ionic compound Ionic compound + Ionic compound Which of the following is true about this type of chemical reaction? (4 points) 1. It is a single replacement reaction, and all four compounds are different. 2. It is a double replacement reaction, and all four compounds are different. 3. It is a single replacement reaction, and each compound has the same set of ions. 4. It is a double replacement reaction, and each compound has the same set of ions.

Answer 41

**2.** It is a double replacement reaction, and all four compounds are different.

Question 42

Potassium hydroxide (KOH) reacts with sulfuric acid (H₂SO₄) to produce potassium sulfate (K₂SO₄) and water. What best describes this reaction? (4 points) 1. A single replacement reaction occurs because potassium ions bond with sulfate ions to form a salt. 2. A double replacement reaction occurs because potassium ions bond with sulfate ions to form a salt. 3. A single replacement reaction occurs because potassium is more reactive than hydrogen. 4. A double replacement reaction occurs because potassium is less reactive than hydrogen.

Answer 42

**2.** A double replacement reaction occurs because potassium ions bond with sulfate ions to form a salt.

Question 43

All combustion reactions release energy. (2 points) True or False

Answer 43

True

Question 44

Which of the following shows a valid combustion reaction? (4 points) 1. 2Al + 2O₂ → 2AlO + O₂ 2. C₂H₄ + 3O₂ → 2CO2 + 2H₂O 3. 2CH₄ + O₂ → 2CO + 4H₂ 4. Ca + O₂ → CaOH

Answer 44

**2.** C₂H₄ + 3O₂ → 2CO2 + 2H₂O

Question 45

What is true when an element is oxidized? (4 points) 1. It bonds with the hydroxide ion. 2. It loses electrons to another element. 3. It reacts with oxygen gas. 4. It takes electrons from another element.

Answer 45

**2.** It loses electrons to another element.

Question 46

Which substances in the list can be some of the reactants and products in the same combustion reaction? (4 points) 1. 1, 2, and 3 2. 2, 3, and 6 3. 1, 4, and 5 4. 1, 2, and 5

Answer 46

**2.** 2, 3, and 6

Question 47

When potassium metal is placed in water, a large amount of energy is released as potassium hydroxide and hydrogen gas are produced in the reaction 2K_(s) + 2H₂O_(l) → 2KOH_(aq) + H_2(g). Your lab partner says this is a redox reaction and a combustion reaction. Do you agree? Defend your answer by explaining whether or not it meets the requirements of each type of reaction. (6 points)

Answer 47

The reaction is a combustion reaction since there is a reaction with oxygen (the potassium metal interacts with the oxygen in water); furthermore, it releases energy, which is another characteristic of a combustion reaction. However, the lab partner is correct; the reaction is also a redox reaction. In the reactants, the 2K has an oxidation number of 0 since it is a neutral element. However, in the product, potassium in 2KOH has an oxidation number of +2 (+1 \* 2), which means an oxidation reaction occurred. Ogyen had a -4 (-2 \* 2) oxidation number in the reactants and -4 oxidation number in the product, so it did not change. Hydrogen, which originally had a +4 (+1 \* 2 \* 2) oxidation number, has a +2 oxidation number in 2KOH. Since hydrogen had an increase in electrons, a reduction occurred, making it the oxidation agent for potassium; however, since potassium had a decrease in electrons, an oxidation reaction occurred, making it the reduction agent.

Question 48

What is the oxidation number of manganese in MnO₄¹⁻? (4 points) 1. +3 2. +4 3. +7 4. +8

Answer 48

**3.** +7

Question 49

What substance is reduced in the reaction 2Fe²⁺ + Cl₂ → 2Fe³⁺ + 2Cl−? (4 points) 1. Cl₂, because it gained electrons 2. Cl₂, because it lost electrons 3. Fe²⁺, because it gained electrons 4. Fe²⁺, because it lost electrons

Answer 49

**1.** Cl₂, because it gained electrons

Question 50

Why are redox reactions used in batteries? (4 points) 1. The attraction between charged ions releases energy. 2. The movement of electrons creates an electric current. 3. The reactions are extremely exothermic, producing an electric current. 4. The reactions are extremely endothermic, inducing the movement of electrons.

Answer 50

2. The movement of electrons creates an electric current.

Question 51

Read the following chemical equation: **2Co + 3F₂ → 2CoF₃** Which statement best identifies and describes the reducing agent in the reaction? (4 points) 1. Co is the reducing agent because its oxidation number increases. 2. Co is the reducing agent because its oxidation number decreases. 3. F2 is the reducing agent because its oxidation number increases. 4. F2 is the reducing agent because its oxidation number decreases.

Answer 51

**1.** Co is the reducing agent because its oxidation number increases.

Question 52

In which of the following reactions is chlorine (Cl) oxidized? (4 points) 1. Br₂ + 2Cl⁻ → Cl₂ + 2Br⁻ 2. Cl₂ + 2e− → 2Cl− 3. 2ClO₃⁻ + 12H+ → Cl₂ + 6H₂O 4. 2Na + Cl₂ → 2NaCl

Answer 52

**1.** Br₂ + 2Cl⁻ → Cl₂ + 2Br⁻

Question 53

Which of the following reactions could be used to power a battery because of the transfer of electrons? (4 points) 1. Pb₂²⁺ + 2Br⁻ → PbBr 2. CaCl₂ + 2NaOH → Ca(OH)₂ + 2NaCl 3. KOH + HCl → KCl + H₂O 4. Zn + Cu²⁺ → Zn²⁺ + Cu

Answer 53

**4.** Zn + Cu²⁺ → Zn²⁺ + Cu

Question 54

Why are redox reactions used in batteries? (4 points) 1. The attraction between charged ions releases energy. 2. The movement of electrons creates an electric current. 3. The reactions are extremely exothermic, producing an electric current. 4. The reactions are extremely endothermic, inducing the movement of electrons.

Answer 54

**2.** The movement of electrons creates an electric current.

Question 55

What are the characteristics of a combustion reaction?

Answer 55

Combustion Reaction: **Reaction in which a substance reacts with oxygen gas** 1. reacts with oxygen 2. releases a large amount of energy (light/heat) 3. Exothermic

Question 56

What is an Organic Combustion Reaction?

Answer 56

*Compounds contain carbon covalently bonded (and sometimes hydrogen)* ***CxHx + O₂ → H₂O + CO₂*** _[Hydrocarbon](https://www.notion.so/03-07-Honors-Organic-Chemistry-08f459a3e3d64f38aab99ecb50ec5895) combustion:_ * products: carbon and water _Cellular Respiration:_ * organic compounds (glucose; C6H12O6) + oxygen = energy

Question 57

What is an inorganic combustion reaction?

Answer 57

**A + O2 → AOx** * burn-in oxygen * synthesis reactions * React with oxygen = energy

Question 58

What are the formulas for organic and inorganic combustion reactions?

Answer 58

CxHx + O₂ → H₂O + CO₂ (organic compounds) A + O2 → AOx (inorganic compounds)

Question 59

What is a redox-reaction?

Answer 59

`Oxidation-Reduction (redox) reaction: **Reaction electrons exchanged from one substance to another**

Question 60

What is oxidation? What is the reduction?

Answer 60

***_Oxidation_*: substance loses one+ electron during reaction → higher, positive oxidation number** * many metals: react with oxygen → ionic metal oxide compound ***_Reduction_*: substance gains one+ electron → lower, negative oxidation number** * decrease charge → decrease reduction _Oxidation and Reduction go together:_ * one substance must O if another R

Question 61

What is the difference between a single replacement or double replacement reaction?

Answer 61

Single Replacement & Redox * most common neutral atom → electrostatic charge → new compound Double Replacement & Redox * ions do not change charge

Question 62

What is the oxidation number and what are the 5 rules?

Answer 62

_Oxidation Number:_ a number assigned to an atom of an element that represents the number of electrons lost or gained 1. **_Neutral Elements:_** Standard state Oxidation Number: **0** * O2 * Na * F2 * S8 * P4 2. **_Oxygen_:** Oxidation Number: **-2** except in peroxides: **-1** * H20 (O = -2) * CaO (O = -2) * H2O2 = (O = -1) 3. **_Monatomic Ions:_** Oxidation Number: **equal to charge as ion** * NaCl ( Na = +1, Cl = −1) * CaBr2 (Ca = +2, Br = −1) * Ag+ (Ag = +1) * Al3+ ( Al = +3) 4. **_Covalent Compounds:_** Present compound is ionic with more electronegative element froming anion Oxidation Number: **equal to "charge" of ion** * CCl4 ( C = +4, Cl = −1) * NH3 ( N = −3, H = +1 ) 5. **_All Elements:_** All oxidation numbers: **add up to total charge compound**

Question 63

What are oxidation and reduction? What is the reduction agent and the oxidation agent?

Answer 63

***_Oxidation_*: substance loses one+ electron during reaction → higher, positive oxidation number** * many metals: react with oxygen → ionic metal oxide compound ***_Reduction_*: substance gains one+ electron → lower, negative oxidation number** * decrease charge → decrease reduction **Reduction Agent** * * * Causes another substance to reduce (*not reduce itself)* * Reducing agent: reactant is oxidized **Oxidization Agent** * * * Causes another substance to oxidize (*not oxidized itself)* * Oxidization Agent: reactant is reduced

Question 64

What are nuclear reactions?

Answer 64

Nulceus split apart/smaller nuclei are combined * changes element's identity * protons and neutrons gained lost by atoms over the course of the nuclear reaction "lost" protons become new particles

Question 65

What is Einstein's Formula and how does it relate to mass and energy?

Answer 65

***E = mc²*** *Multiplying loss of mass by speed of light squared = amount of energy* _Relationship between mass and energy_ Regular chemical reaction: **Mass and Energy both conserved** Nuclear Reaction: * mass converted to energy

Question 66

What is fission?

Answer 66

Elements - greater mass * often unstable & radioactive undergo reactions: _FISSION_ 1. break apart into smaller atoms 2. "missing" mass = **energy** *Multiplying loss of mass by speed of light squared = amount of energy*

Question 67

What is _Fusion_?

Answer 67

Occurs Sun * (theory) replicate on earth * * * **Form one larger element from smaller molecules** * nuclei hurled at each other high speed * new nucleus: less mass single nuclei extra mass: energy *Helium = hydrogen + hydrogen*

Question 68

What are the advantages and disadvantages of fission?

Answer 68

_Advantages of Fission_ 1. small hydrogen isotopes plentiful 2. easy obtain _Disadvantages of Fission_ 1. unstable; not easy control

Question 69

Define Strong Nuclear forces:

Answer 69

**Attractive forces hold the nucleus of an atom together** hold subatomic particles together inside the nucleus Protons: positive → repel → electromagnetic forces Strong nuclear forces → override electromagnetic repulsion * proton stay close in the nucleus * * * 1. Strongest four fundamental forces 2. Shortest range

Question 70

Define Weak Nuclear Foces?

Answer 70

What: 1. **responsible for different types of particle decay** 2. **Radioactivity** * when nucleus atoms break down * released charged particles * * * 1. Very short range

Question 71

Define electromagnetism:

Answer 71

**Forces that occur when an electromagnetic field interacts with electrically charged particles** _Examples_: * electricity * magnetism * static * light * electromagnetic spectrum * molecular bonds * * * 1. Second strongest 2. Only force both attract and repel (depending on charge) 3. Very long range

Question 72

Define Gravity:

Answer 72

**an attraction force that pulls two objects together** weaker the farther objects are apart weight: a *combination of mass and gravitational force* * * * 1. Weakest 2. longest range

Question 73

Define Radioactive decay:

Answer 73

nuclei break down to form a different substance and release radiation in process.

Question 74

What is Alpha decay?

Answer 74

Alpha (α) * * * The steam of alpha particles * 2 protons & two neutrons * positive charge *Atom releases alpha particle:* * atomic number decrease -2 * Mass number decrease -4 _Properties_: 1. **high kinetic energy** 2. cause **damage surface** (skin and living tissue) 3. **easy shield against** * not penetrate paper * move through air → neutral helium atoms

Question 75

Define Beta Decay?

Answer 75

**Beta (β)** * * * Steam beta particles * fast-moving electrons released from the nucleus when neutrons break apart into: 1. 1 proton 2. 1 election Negative beta particle: * one more proton and one less neutron _Properties:_ 1. **negative charge** 2. **faster than alpha** 3. more **difficult protect against** * penetrate cloth and paper * kill cells * not penetrate aliminum

Question 76

What is Gamma decay?

Answer 76

Gamma (γ) * * * Gamma Radiation: given off during different types of nuclear decay * electromagnetic waves * high frequency * greater energy than ultraviolent/x-rays _Properties_: 1. high energy 2. no mass or charge 3. penetrate through most materials * damange * not penetrate lead

Question 77

Define transmutation:

Answer 77

the changes of identity of an element due to radioactive decay

Question 78

What are Uranium (Alpha Decay) Transmutations?

Answer 78

Uranium [Alpha Decay] * * * **Radioactive uranium-238:** goes through alpha decay → alpha particle 1. 2 protons 2. 2 neutrons 3. leave thorium-234 During reaction: energy released (kinetic) * atomic number decrease -2 * mass number decrease -4

Question 79

What is Thorium (Beta) Decay?

Answer 79

Thorium [Beta Decay] * * * **Thorium-234:** beta particle * atomic number **increases +1** * mass number **same**

Question 80

Define the rate of Radioactive Decay:

Answer 80

_Measure_: **HALF-LIFE** * the time it takes for the radioactivity level of an isotope * decrease to half its original value _Property_: 1. isotope is constant 2. independent of external conditions **Radium-226** → half-life 1,620 years half given sample decay half end 1,620 years