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    Pre-lab 4

    Title: Periodic Trends

    Date: 9/12/18

    Unknown: N/A

    Purpose: The purpose is to observe chemical properties of elements in periods (rows) and in

    groups/families (columns).

    Balanced Equations:

    Part 1: Chemical Properties of the Alkaline Earth Metal Nitrates

    Mg(NO3)2(aq) + Na2CO3(aq)  MgCO3(s) + 2NaNO3(aq)

    Ca(NO3)2(aq) + Na2CO3(aq)  CaCO3(s) + 2NaNO3(aq)

    Ba(NO3)2(aq) + Na2CO3(aq)  BaCO3(s) + 2NaNO3(aq)

    Part 2: Chemical Properties of the Halides

    NaCl(aq) + AgNO3(aq)  AgCl(s) + NaNO3(aq)

    NaBr(aq) + AgNO3(aq)  AgBr(s) + NaNO3(aq)

    NaI(aq) + AgNO3(aq)  AgI(s) + NaNO3(aq)

    Part 3: Reactivity of Third Period Elements with Oxygen

    2 Mg(s) + O2(g)  2 MgO(s)

    4 Al(s) + 3 O2(g)  2 Al2O3(s)

    Si(s) + O2(g)  SiO2(s)

    Part 4: Reactivity of Third Period Elements with Hydrochloric Acid

    Mg(s) + 2 HCl(aq)  MgCl2(aq) + H2(g)

    2 Al(s) + 6 HCl(aq)  2 AlCl3(aq) + 3 H2(g)

    Si(s) + 4 HCl(aq)  SiCl4(aq) + 2 H2(g)

    Table of Chemical and Physical Properties:

    Chemical Name Molecular

    Weight

    Boiling Point Density Safety

    Barium nitrate

    Ba(NO3)2

    261.34

    529 C 3.24 g/cm

    3 Poisonous. Do

    not mix with

    flammable

    materials.

    Silver nitrate

    AgNO3

    169.87 440 C 4.35 g/cm3 Corrosive and

    toxic. Avoid

    skin contact.

    Sodium Chloride

    NaCl

    58.44 801 C (melting

    point)

    2.16 g/cm3 Nonhazardous

    Magnesium

    Mg

    24.31 650 C (melting

    point)

    1.738 g/cm3 Flammable. Do

    not stare are

    flame during

    reaction with

    magnesium and

    oxygen

    Calcium

    Ca

    40.08 842 C (melting

    point)

    1.54 g/cm3 Flammable

    gases produced

    with in contact

    with water

    Aluminum

    Al

    26.98 2460 C 2.7 g/cm3 Flammable

    Silicon

    Si

    28.09 2355 C 2.33 g/ml Nonhazardous

    Oxygen

    O

    15.999 u 90.188 K 1.429 g/L Flammable gas

    Hydrochloric

    acid

    HCl

    36.46 110 C 1.18 g/cm3 Toxic and

    corrosive. Can

    cause irritation

    or burns to skin.

    Procedure Observation

    Part 1

    1. Add 1ml of each solution to each labeled test tubes

    2. Add about three drops of solution from tube 4 into tubes 1-3 and record

    observations.

    Part 2

    3. Repeat steps 1&2 for part 2 with different solutions

    Part 3

    4. On a watch glass, add small pieces of magnesium, aluminum and silicon and

    observe physical appearances.

    5. Take turns placing each substance over an open flame and record

    observations.

    Part 4

    6. Place a small piece of magnesium, aluminum, and silicon in separate test

    tubes and label appropriately.

    7. Place 1ml of HCl into each test tube and record observations.

    Data Collected:

    Part 1

    Aqueous

    substances

    Observations after reacting with 0.02 M Na2CO3

    Mg(NO3)2

    Ca(NO3)2

    Ba(NO3)2

    Part 2

    Aqueous

    substances

    Observations after reacting with 0.10 M AgNO3

    NaCl

    NaBr

    NaI

    Part 3

    Metallic

    substances

    Observations during and after reaction with atmospheric O2

    Mg

    Al

    Si

    Part 4

    Metallic

    substances

    Observations during and after reaction with aqueous HCl

    Mg

    Al

    Si

    Discussion:

    Conclusion:

    Date Completed & Signature:

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