Chem Unit Review

what is the order of the periodic table?

alkali metals, alkali earth metal, transition metals

, metalloids, non-metals, noble gases,

Define a physical and chemical change

Physical: Matter changes form but not identity

Chem: Chemical change forms new products

State some examples of physical properties

Colour/Smell

Lustre: Shiny/dull

Clarity: Transparent, tranluscent, opaque

Malleability: Bends?

Density/State: Heaviness and state it’s in (solid, liquid, gas)

State some examples of Chemical properties

Flammability

Toxicity

Reactivity

Define Phy and Chemical Properties

Phys: Describes the substance itself

Chem: Desrcibes how substance reacts with other substances

Define Matter, Properties, and Change Flowchart

Matter: anything that takes up space

Pure Substance: All particles are made of the same element

Mixture: 2+ pure substances

P:S

Element: Subtances/atoms with the same atomic # (Sodium, Silver, anything on periodic table)

Compound: 2+ elements chemically combined (Carbon dioxide, Water)

Mixture:

-Homogenous: You can’t see different parts of the mixture (Apple juice, Chocolate milk)

-Hetero: you can see diff parts (salad, cookie)

Differences between ionic and covalent bonding: What is it?

Ionic: Tranfer electrons, between met and non, high melting/boil points, solid at room temp, electrical conductors

Covalent: Sharing of electrons, between 2 nons, low melting/boil points, can be gases, liquids, soft solids at room temp, poor conductors

Clearly explain why an oxygen ion has a charge of 2-

An oxygen ion has a charge of -2 because for an ion to be stable, it must have a full outer shell of 8 electrons. It is easier for oxygen to gain 2 negatively charged electrons rather than lose all 6 electrons.

-Additionally, you can subtract protons (positively charged) and electrons to get the electron charge (+8 protons - 10 electron = -2)

Stomach acid has a pH of around 3 while Tums to cure heart burn has a pH of about 9. How many times more acidic is stomach acid than tums? Use pH scale

Stomach acid is 1, 000, 000x more acidic than Tums. Fidn both numbers on scale and count how many times it goes up (x10). 3 and 9 are 6 away from each other so 10^6= answer.

What are the colours for the pH test: Bromothymol blue, phenolphthalein, Litmus paper

-_-_-_-_-_-_-_-_ Acidic colour , Nuetral, Basic (high pH)

Litmus Paper Red N/A Blue

Phenolphthalein Colourless Same Pink

Bro Blue Yellow Green Blue

Explain the diff between binary acid and oxyacid and give an example of each

A binary acid contains only two elements (hydrogen and a nonmetal) and lacks oxygen (Hydrochloric acid (HCl) prefix hydro -element- suffix -ic

An oxyacid contains hydrogen, oxygen, and at least one other nonmetallic element. ( Nitric acid (HNO)

(no prefix but has the name of the polyatomic ion plus -ic suffix) chloric acid

If a block of iron is left undisturbed in moist air it will start to rust as it reacts with the oxygen in the air. Will it gain or lose mass? Explain

The block will have it’s initial weight of blank.

The iron will begin to slowly react with the oxygen and water molecules in the air (causing a synthesis reaction).

Now, the iron will have more weight due to the bonding of oxygen + iron and the rust on top shows that.

What gas goes “pop” when tested with a flaming splint.

Hydrogen

Explain 2 diffz between the flaming and glowing splint test

-Flame: looks for CO2 or Hydrogen, flame will be blown out/make a loud pop noise

-Glow: Oxygen, will re-light when splint comes in contact

How can u tell if a reaction is a combustion reaction and what are 2 key compounds that are always produced during combustion of a hydrocarbon?

-Usually involves a fuel reacting with oxygen

-A combustion reaction will always form CO2 and H2O

-Also produces energy in the form of heat and light

How can u tell if a reaction is a nuetralization reaction and what are 2 key compounds that are always produced during the reaction?

This reaction happens between an acid and a base: when hydrochloric acid (HCL) reacts with sodium hydroxide (NaOH) they combine to form water and sodium chloride which is just table salt

-The two key compounds are with produced are water and a salt

Compare and Contrast Acids and Bases

Acids + Bases: Both conduct electricity, both react with each other to nuetralize and form a water and salt, change colour of pH indicators

Diffs: Acids-Below 7 on pH scale , react with active metals , produce hydrogen atoms

Bases: Above 7 on pH scale , do not react in this manner, hydroxide ions

State three properties of acids and bases

Acids: taste sour (in many citrus and other fruit juices), have pH below 7, donate hydrogen ions

Bases taste bitter (household items like soap), feel slippery, have pH above 7 and accept hydrogen ions or donate hydroxide ions