Homework: Review of Mixtures Unit For Test

Last updated about 1 year ago

5 questions

Homework: Review of Mixtures Unit For Test

Last updated about 1 year ago

5 questions

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
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
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.
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

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

Covalent compounds have a nonmetal bonded to another nonmetal
Examples: CO2

SET 1
A) What is the atomic number __________
B) What is the atomic mass __________
C) How can we determine the number of neutrons in an element __________
D) The number of protons typically equal the number of __________
E) Isotopes are atoms with the same atomic number but with a different __________
F) Ions can occur when atoms interact. Cations are formed when metals __________. Anions are formed when (typically) nonmetals __________.

SET 2
A) What is the atomic mass of Hydrogen (H) __________
B) What is the atomic number of Bromine (Br) __________
C) How many neutrons does Nickel (Ni) have __________
D) How many electrons should Bromine (Br) have by looking at its atomic number __________
E) An isotope of Phosphorus-31 could be __________

SET 3
A) Which of these is an ionic compound (metal + nonmetal) __________
B) Which of these is an covalent compound (nonmetal + nonmetal) __________
C) Which is the correct model for CrO4 __________

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.

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

Draggable item		Corresponding Item
Ms. Phoebe has a mixture of salt, sand, 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. Maddy has a mixture of two liquids that have separate boiling points.