Week 2 Chemistry

Question 1

What is matter?

Answer 1

anything that takes up space and has a mass

Question 2

What are atoms?

Answer 2

Smallest unit of matter known as an atom.

Question 3

What are the three states of matter?

Answer 3

Solids, Liquids, Gasses

Question 4

What is the relationship between atoms and hot and cold?

Answer 4

Atoms are always moving (vibrating). The movement of an atom is what we refer to as heat.

Question 5

How do atoms form solids?

Answer 5

Atoms link together into molecules using covalent bonds. These bonds are formed because almost no loose atoms have the amount of electrons they prefer to have around them

Question 6

What is the structure of atoms?

Answer 6

A single atom is composed of a central nucleus surrounded by clouds of electrons

Question 7

What are protons?

Answer 7

Protons give atoms their identity. They are +ively charged

Question 8

What do the number of protons determine?

Answer 8

It’s atomic number & what element it is. + charge

Question 9

What is the atomic number of an element ?

Answer 9

The number of protons that are present in an atom

Question 10

What are neurons?

Answer 10

No charge but help keep the nucleus together. Neutral. (sub-atomic particle in the nucleus)

Question 11

What is the mass number of an element?

Answer 11

The sum of protons and neutrons in the nucleus

Question 12

What is an isotope?

Answer 12

Contain the same number of protons but different number of neurons. (not all cases)

Question 13

What is the atomic mass of an element?

Answer 13

It equals the number of protons and neutrons within the nucleolus (p+n) = atomic mass

Question 14

What are electrons?

Answer 14

A subatomic particle (can have both mass and no mass)

The number of electrons is always equal to the number of protons found in an element - charge

Question 15

How was electrons arranged around the nucleus

Answer 15

First shell  (2 electrons)
Second shell (max 8 electrons)
Valence shell 8 electrons. :(octet rule)

Question 16

What are three categories of pure substances?

Answer 16

Elements, molecules, compounds

Question 17

What is an element?

Answer 17

Usually refers to a substance made up of one type of atom and the properties of that substance

Question 18

Describe a molecule

Answer 18

Is a substance made up of two or more atoms which are either from the same element or different element that form a unit

Question 19

Describe a compound

Answer 19

A substance made up of two or more atoms which form different elements

Question 20

Describe metabolism

Answer 20

The chemical processes that occur within a living organisms in order to maintain life

Question 21

Define Catabolisim

Answer 21

The break down of complex molecules

Question 22

Define Anabolism

Answer 22

systhesis of complex molecules (build up)

Question 23

What are electron shells?

Answer 23

Holds electrons 2:8:8 octet rule

Question 24

What is the outer most shell that contains electrons called?

Answer 24

Valence shell (third shell)

Question 25

What element category needs full electron shells?

Answer 25

Nobel gases, 8 in the vallance shell

Question 26

What is a mixture?

Answer 26

2 or more elements that are physically combined together. But are not bound by chemical bonds.

Question 27

What can mixtures contain?

Answer 27

Solids, liquids and gasses, either alone or in combination

Question 28

What is a solvent?

Answer 28

Liquid (or gas) in which another substance is dissolved to form a solution

Question 29

How does water act as a solvent?

Answer 29

H2o is charged, it disrupts the bonds resulting in individual molecules floating around.

Question 30

What are colloids?

Answer 30

A mixture of solute and solvent. The particles are large enough to scatter light as it passes through

Question 31

What are suspensions?

Answer 31

A mixture of particles in a liquid for a period of time, will eventually settle out of liquid

Question 32

What is a mole?

Answer 32

It's a measurement chemist use

Question 33

What is concerntration?

Answer 33

The number of molecules present in a given volume. Can be described in %

Question 34

What is the definition of molarity?

Answer 34

Molecules in a reaction, measuring them in relation to weight to express the concentration of a chemical

Question 35

What is the formula of the mole?

Answer 35

atomic number + atomic number = molecular weights. (Actual weight) - provided in question. Actual weight / molecular weight = X X/Litres = Mole

Question 36

What are the types of chemical bonds?

Answer 36

Ionic bonds Covalent bonds Metallic bonds Hydrogen bonds

Question 37

What is an Ionic Bond?

Answer 37

is the complete transfer of valence electron(s) between atoms. Valence shell of 7 electrons

Question 38

What is an Covalent Bonds

Answer 38

They're not physically exchanged. They share electrons to fill there valance shell.

Question 39

Describe Non-Polar Covalent Bonds

Answer 39

Equal sharing of electrons so the resulting molecule has no charge associated with it.

Question 40

Describe Polar Covalent Bonds

Answer 40

The sharing of the electrons is uneven.

Question 41

Describe Metallic bonds

Answer 41

Metals tend to have a few extra electrons in there valence shells.

Question 42

Describe Hydrogen Bonding

Answer 42

Weaker interactions that alter the way molecules interact with eachother.

Question 43

What are the two components to a chemical reaction?

Answer 43

The reactant | The product

Question 44

What is a chemical reaction?

Answer 44

The bonds that hold atoms together are broken and rearranged to make new substances.

Question 45

What is energy?

Answer 45

The capacity for doing work or causing change.

Question 46

Energy comes from two forms, what are they?

Answer 46

Potential energy | Kinetic energy

Question 47

What is potential energy?

Answer 47

Energy stored by matter due to it's position

Question 48

What is kinetic energy?

Answer 48

Energy associated with matter in motion

Question 49

What is chemical energy?

Answer 49

Form of potentislal energy that is stored in chemical bonds. (endothermix and exothermic)

Question 50

Describe exothermic

Answer 50

An exothermic reaction is a chemical reaction that releases energy through light or heat

Question 51

Describe endothermic

Answer 51

Endothermic process is any process which requires or absorbs energy from its surroundings, usually in the form of heat

Question 52

What are different types of reactions?

Answer 52

Synthesis Decomposition Exchange Reversible

Question 53

Describe Synthesis reaction

Answer 53

Two or more atoms/molecules are bonded together to form a more complex molecule

Question 54

Describe Decomposition reaction

Answer 54

A larger molecules broken apart into simpler substances

Question 55

Describe Exchange reaction

Answer 55

What one atom/functional group replaces another in a compound. Both synthesis and decomposition

Question 56

Describe Reversible reaction

Answer 56

A reaction that can proceed in both direction

Question 57

What is activation energy

Answer 57

A type of reaction to get bonds between atoms to form or break, a collision with enough energy is required.

Question 58

Describe catalysts

Answer 58

Is a chemical substance that acts to lower the activation energy required for certain chemical reaction Catalysis is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst,

Question 59

What is an enzyme?

Answer 59

An enzyme is a protein that acts as a catalyst

Question 60

How do enzymes work?

Answer 60

Attracts reactants binding them at the active site, working on them, producing the products then releasing the products. Lock & key