Homework: Review of Mixtures Unit For Test

Posljednje ažuriranje over 1 year ago

Create a model of this atom
Zr₂H₂O₇K₂

Biblioteka

Homework: Review of Mixtures Unit For Test

Posljednje ažuriranje over 1 year ago

Atomic number = the number of protons (+) in an atom

It is the number at the top of an elements square
Example: Tungsten (W) has an atomic number of 74

null

Atomic mass = the number of protons and neutrons in an atom

The # of neutrons can be calculated by subtracting the atomic mass and atomic number
Example: Silver (Ag): 108 - 47 = 61 neutrons

null

The periodic table reflects neutral atoms & the # protons = the # of electrons to present a neutral charge.

Example: Phosphorus has an atomic number of 15, which means in a neutral atom is has 15 protons and 15 electrons.

null

Isotopes are atoms that have the same number of protons (atomic number) and identity, but a different number of neutrons (atomic mass).

Example: carbon-12 and carbon-13 are isotopes of one another because they both have the same atomic number but a different number of neutrons

null

Ions can occur when atoms interact. Cations are formed when metals lose electrons. Anions are formed when (typically) nonmetals gain electrons.

Example: Na can lose an electron & become the cation Na⁺
Example: Cl can gain an electron & become the anion Cl^-

Ionic compounds have a metal and nonmetal bonded together.

Groups 1 and 2 are metals
Groups 14 to 18 are nonmetals
Example: NaCl

null

Covalent compounds have a nonmetal bonded to another nonmetal

Examples: CO₂

null

Create a model of this atom
Zr₂H₂O₇K₂

Purse substances and Mixtures

There are 2 main types of substances: pure substances and mixtures.

Pure substances can be elements, molecules of elements, or molecules of compounds.

Mixtures are a combination of 2 or more pure substances that are mixed together in the same area, yet the substances are not chemically combined by bonds. These substances do not change their chemical identity.

Mixtures include 2 or more different elements, 2 or more different compounds, or 2 or more different elements and compounds all in the same area.

Mixtures have different names which are determined by their particle size.

A suspension is when big particles or chunks of something float in a liquid, like the mustard in a mac salad.
A solution is when very small particles are mixed with a liquid.
Colloids are when you take 2 materials that do not dissolve and you make the particles so small that they cannot separate.

Mixtures can be separated by physical and chemical properties. In distillation, a mixture is heated and the temperature is monitored. As a substance reaches its boiling point, it will evaporate and turn into steam. This steam will enter a condenser that cools the steam, which then liquifies and falls into a receiving flask. At the end, the original flask will have one substance that has a higher boiling point and did not evaporate (called the residue) and the receiving flask will have a different substances with a lower boiling point that evaporated (the distillate). This process is used to separate petroleum (oil) into its valuable components like propane, diesel fuel, waxes and lubricants.

null

Create a model of...
A mixture of Compounds
A mixture of Elements
A mixture of Elements and Compounds
Use atoms from the periodic table to contrive your models

Match the scenario to the technique that can separate it

Stavka koja se može prevući		Odgovarajuća stavka
Mrs. Bello has a homogenous mixture of salt and water.		Filter the mixture in a filter paper to collect the solid residue in the paper and the liquid filtrate in the flask
Ms. Phoebe has a mixture of salt, sand, and water.		Use distillation to separate the mixture by vaporizing one, while keeping the other in the flask. The vaporized one will condense in a condenser and become a separated liquid.
Ms. Maddy has a mixture of two liquids that have separate boiling points.		Use evaporation, allowing the liquid to vaporize into a gas and the solid to stay
Mr. Guesno wants to separate a heterogenous mixture of sand and water.		First filter one substance out using a filter paper. Then with the remaining mixture, which is now liquid and a dissolved solute, evaporate the liquid. You should have crystals of solute remaining.