Balancing Equations

Question 1

chemical reaction

Answer 1

When bonds are broken, and new bonds are formed, resulting in new substances

Question 2

chemical equation

Answer 2

A representation of a chemical reaction using chemical formulas

Question 3

balanced chemical equation

Answer 3

An equation where the number of atoms on both sides is equal, following the law of conservation of mass

Question 4

Reactant in a chemical reaction

Answer 4

A substance that STARTS the reaction and is consumed during the process (Left side)

Question 5

product in a chemical reaction

Answer 5

A substance that is formed because of the chemical reaction (Right side)

Question 6

What is a Synthesis reaction (show its general form)

Answer 6

A reaction in which two or more substances combine to form a new compound

General form:
A+B—>AB

Question 7

What is a Decomposition reaction (show its general form)

Answer 7

A reaction where one substance breaks down into two or more simpler substances

General form: AB—>A+B

Question 8

What is single displacement reaction (show its general form)

Answer 8

A reaction in which one element replaces another element in a compound

General form: A+BC—>AC+B

Question 9

What is double displacement reaction (show its general form)

Answer 9

A reaction where two compounds exchange ions to form new compounds

General form: AB+CD—>AD+BC

Question 10

What is a combustion reaction (show its general form)

Answer 10

A reaction in which oxygen reacts with a compound, releasing energy in the form of heat and light

General form:
Fuel+O2—>CO2+H2O

Question 11

Why do we need to balance chemical equations

Answer 11

To ensure the total number of atoms of each element is the same on both sides of the equation

Question 12

What is the relationship between an atomic number and its mass number

Answer 12

Mass number will always be greater than the atomic number

Question 13

How do you determine the number of neutrons in an atom if you are given the atomic number and mass number

Answer 13

Mass number - Atomic number = neutrons

Question 14

Explain the difference between atomic number and mass number with examples

Answer 14

Atomic number: How many protons and electrons an element has

Mass number: An element is how you find protons (Mn - An)

Eg Carbon
Atomic # = 6
Mass # = 12

Question 15

Defines isotopes

Answer 15

Atoms of the same element with different numbers of neutrons

Question 16

Mass number

Answer 16

Total number of protons+neutrons

Question 17

Atomic Number

Answer 17

Number of protons

Question 18

Most abundant isotope

Answer 18

Protium

Question 19

Atomic notation

Answer 19

Mass number: Top
Atomic number/Protons: Bottom
Atomic symbol: Middle

Question 20

Isotopes differ in

Answer 20

Mass number

Question 21

Primary different between isotopes of an element

Answer 21

Number of protons

Question 22

Finding the average atomic mass using isotopes

Answer 22

Eg.
carbon 12 (98.9% x100)
Carbon 14 (1.1% x100)

12x0.989 + 14x0.011 =12.022 12.022amu

Question 23

Explain why the atomic mass of an element is not always a whole number, using isotopes as an example

Answer 23

Atomic mass is the weight average of all the naturally occurring isotopes of an element

Eg.
Carbon has isotopes c-12 and c-14
Average mass = 12.011

Question 24

Atomic mass unit (amu) is defined based on which isotope

Answer 24

Carbon-12

Question 25

1 atomic mass unit (amu) is equal to?

Answer 25

One-twelfth the mass of a carbon-12 atom

Question 26

Atomic mass

Answer 26

Average mass of all its isotopes

Question 27

Orbitals for s,p,d,f

Answer 27

S: 1 P: 3 D: 5 F: 7

Question 28

Subshells eg (N=1 includes)

Answer 28

N=1: S (2 electrons) N=2: S,P (8 electrons) N=3: S,P,D (18 electrons) N=3: S,P,D,F (32 electrons)

Question 29

Order of polytomic ion naming

Answer 29

Hypo(1), ite(2), ate(3), per(4)

Question 30

Covalent bond

Answer 30

Two non-metals share electrons

Question 31

Ionic bond

Answer 31

A metal transfers electrons to a non-metal

Question 32

Naming covalent compounds

Answer 32

No prefixes are used

Question 33

Naming Ionic compounds

Answer 33

Use prefixes (mono, di, tri, tetra, penta)

Question 34

Ionic compound naming example of N2O

Answer 34

Dinitrogen Monoxide

Question 35

(g) means

Answer 35

Gas

Question 36

(L) means

Answer 36

Liquid

Question 37

(S) means

Answer 37

Solid

Question 38

(Aq) means

Answer 38

Aqueous (dissolved in water)

Question 39

Law of conversation of mass

Answer 39

Matter is neither created nor destroyed in a chemical reaction

Question 40

Scientific notation (directions)

Answer 40

Moving right = Negative Moving left = Positive

Question 41

Standard for (directions)

Answer 41

3.6 x 105 =360000 3.6 x 10-5 =0.000063

Question 42

Diatomic molecules

Answer 42

H,O,F,Br,I,N,Cl

Question 43

Finding Molecular mass

Answer 43

Eg H20 H: 1.008x2 O: 15.999 2.016+15.999=18.015amu

Question 44

Supplement formula (200mg, 149.09 amu, 30.97amu)

Answer 44

1) 30.97 / 149.09 = 0.207 2) 0.207x100 =20.77% 3) 200 / 20.77% = 9.629 4) 9.629x100 = 962.9mg

Question 45

Finding moles

Answer 45

Moles(mol) = mass(g) / molar mass(g/mol)

Question 46

Aufbau principle

Answer 46

Electrons fill the lowest-energy orbitals first before moving to the higher-energy orbitals

Question 47

Subshells for S,P,D,F

Answer 47

S: 2 P: 6 D: 10 F: 14