Chemistry

Question 1

Mass vs weight

Answer 1

Mass: the quantity of matter an object contains

Weight: the pull of gravity on an object of given mass

Question 2

Mixture(3) vs substances(2)

Answer 2

Mixture
- can be separated by physical means
- 2 or more diff substances
- When mixed together, still retain it’s own qualities

Substance
- consists of 1 element
- the composition remains the same throughout

Question 3

2 types of mixture and differentiate them

Answer 3

Homogeneous: uniformly distributed; can be separated through evaporation

Heterogeneous: visually distinguishable

Question 4

Describe a solution and give an example

Answer 4

It consists of solute (substance being dissolved) and a solvent. Filter is not possible. Salt and water

Question 5

2 types of heterogeneous and define them and give example

Answer 5

Colloids: filter not possible, scatter light, very dense, remain suspended
- milk, smoke, cream

Suspension: “shake well before using”; filter is possible
-blood, oil and water

Question 6

What ate the 2 types of substance

Answer 6

Elements and Compounds

Question 7

Elements vs Compounds

Answer 7

Elements: 1 type of atom; cannot be broken down

Compound: formed when 2 or more substances are formed chemically

Question 8

Elements vs Compounds

Answer 8

Elements: 1 type of atom; cannot be broken down

Compound: formed when 2 or more substances are formed chemically

Question 9

3 types of elements (3)

Answer 9

Metals: hard and shiny elements; good conductor of heat and electricity; tend to lose electrons

Nonmetals: brittle; do not conduct heat and electricity; tend to gain/share electrons

Metalloids: borderline elements between metals and non metals

Question 10

3 types of compounds

Answer 10

Acid, base, salt

Question 11

Acid(4) vs Base(4) vs Salt (3))

Answer 11

Acid: has sour taste, turns blue litmus to red, pH < 7, when concentrated: pH below 0

Base: turns red litmus to blue, Alkalis: strong bases, ph > 7, when concentrated: pH above 14

Salt: produced through the reaction of Base and acid; dissolves in water; conduct electricity

Question 12

These are the properties that distinguish a substance from another substance. Give examples

Answer 12

Intrinsic

Boiling Point, acidity, sweetness, hardness, odor, length

Question 13

These are properties that depend on the amount of matter observed. Give examples

Answer 13

Height, weight, volume, shape, temperature, and length

Question 14

Formula for energy

Answer 14

e = mc²

Question 15

Value of speed of light

Answer 15

3×10⁸ m/s

Question 16

Endothermic vs Exothermic

Answer 16

Endothermic: a reaction where energy is absorbed/taken in

Exothermic: reaction resulting in the release of energy

Question 17

The procedure that is used to quantitatively mix acids and bases

Answer 17

Titration

Question 18

The reaction by which equivalent qualities of an acid and a base react ti form a salt and water

Answer 18

Neutralization

Question 19

The tendency of liquids to dissolve in other liquids

Answer 19

Miscibility

Question 20

The amount of solute that dissolves in a given amount of solvent to produce a saturated solution at a given temperature

Answer 20

Solubility

Question 21

How does heat flows?

Answer 21

From hot body to a cold body

Question 22

Celsius vs Kelvin

Answer 22

Celsius: + 273
Kelvin: -273

Question 23

The basic building blocks of matter

Answer 23

Atoms

Question 24

The number of protons in the nucleus of atom

Answer 24

Atomic number

Question 25

Sum of protons and neutrons

Answer 25

Mass number

Question 26

What do you call an atom that has the same number of protons but different number of neutrons?

Answer 26

Isotopes

Question 27

It is the distribution of electrons in the various energy levels

Answer 27

Electron configuration

Question 28

It is the average path that an electronic takes while traveling around the nucleus

Answer 28

Orbital

Question 29

What is Pauli's Exclusion Principle?

Answer 29

Orbitals can hold no more than 2 electrons

Question 30

It is the electrons in the outermost principal energy level of an atom

Answer 30

Valence electrons

Question 31

Attractive forces is strongest in ____ and weakest in _______

Answer 31

Solid, gas

Question 32

This law states that the volume of a confined gas is inversely proportional to the pressure on it

Answer 32

Boyle's Law

Question 33

In Boyle's Law, when volume increases, pressure ______

Answer 33

Decreases

Question 34

This law states that the volume of a confined gas varies directly with the absolute temperature

Answer 34

Charles Law

Question 35

The attractive force which holds together the atoms of a molecule

Answer 35

Chemical bond

Question 36

3 kinds of chemical bonds and differentiate them

Answer 36

Ionic bond: transfer electrons Covalent bond: sharing electrons Metallic bond: electrons move freely in their valence shell

Question 37

Polar covalent bond vs non polar covalent bond

Answer 37

Polar: unequal sharing of electrons Non polar: equal or almost equal sharing of electrons

Question 38

Avogrado's number

Answer 38

6.02 × 10²³

Question 39

These are the substances that undergo a chem reaction

Answer 39

Reactants

Question 40

A type of chemical reaction wherein a single compound is formed as a result of the chemical combination of 2 elements or compounds

Answer 40

Composition reactions

Question 41

A type of chemical reaction wherein a compound is broken down into simpler substances

Answer 41

Decomposition reactions

Question 42

A type of chemical reaction wherein a more active element dispersed another from its chemical combination

Answer 42

Replacement Reactions

Question 43

A type of chemical reaction where reactants exchange ions, forming two different compounds

Answer 43

Double replacement reactions

Question 44

The property of colloidal to disperse or scatter a beam of light passing through it

Answer 44

Tyndall effect

Question 45

The constant random motion of tiny particles suspended in a fluid caused by molecular collisions

Answer 45

Brownian Movement

Question 46

Process by which solid attracts molecules of gas and liquid to the surface

Answer 46

Adsorption