Date post: | 17-Dec-2015 |
Category: |
Documents |
Upload: | veronica-paul |
View: | 214 times |
Download: | 0 times |
MIDTERM INFO• The Midterm is comprehensive
– County Assessment (1st & 2nd Quarter)• 50 MC Questions & 1 BCR
– Teacher-Designed Exam (1st & 2nd Quarter)• 25 MC Questions
MidTerm Exam Schedule
Tues, 1/15 Full Day –Period 4B Exam during the regular time pd
Wed, 1/16 Day 2 -Examinations – Periods 1 & 2 Schools close 3 hours early.
Thurs, 1/17 Day 3 -Examinations – Periods 3 & 4A Schools close 3 hours early.
Fri, 1/18 Day 4 -Examinations – Periods 5 & 6 Schools close 3 hours early.
Chemistry Midterm Chemistry Midterm ReviewReview
Chemistry Midterm Chemistry Midterm ReviewReview
Day #2Day #2
Agenda• Practice Problems and Review
Sheet
Homework• Review Sheet # 2 – due Monday
or Tuesday
Practice Problem• Difference between an organic
and inorganic cpd is…
• Organic cpds have a C - H bond. Inorganic cpds can have C or H but not this bond.
Review• Show accuracy and precision using
a dart board.
Accuracy vs. Precision• Accuracy – closeness to the actual
value
• Precision – reproducibility
Review• What is the Law of Conservation of
Mass and Energy?
• Mass and energy are neither created nor destroyed during ordinary chemical reactions or physical changes.
• They are just rearranged!• The mass of all the reactants is equal
to the mass of all the products.• The energy that goes in to the reaction
is equal to the energy that comes out.
Answer
Review• Draw Bohr’s Model for Argon
Review• Where on the periodic table do we
find the s, p, d, and f blocks?
Practice Problem• Write the formulas for the
following: (a) barium carbonate, (b) sodium phosphate, and (c) carbon tetrachloride
Answers• a) BaCO3
b) Na3PO4
c) CCl4
Review Question• Name the following compound:
• Cu(BrO3)2
Answer• Copper(II) bromate
Review• List the symbol, charge, and
penetration power for each type of radiation:– Alpha particles– Beta particles– Gamma radiation
NameName SymbolSymbol ChargeCharge MassMass
(amu)(amu)
PenetrationPenetration
Power Power
AlphaAlpha +2+2 44 4.0 cm air 4.0 cm air 0.005 cm 0.005 cm
tissue tissue no no
penetration penetration through leadthrough lead
BetaBeta - 1- 1 0.000550.00055 6-300 cm air 6-300 cm air 0.006-0.5 cm 0.006-0.5 cm
tissuetissue.0005-0.03 .0005-0.03
cm leadcm lead
GammaGamma 00 00 400 m air400 m air
500 cm 500 cm tissuetissue
3 cm lead3 cm leadhttp://www.avon-chemistry.com/nuclear_24.gif
Alpha Radiation α
238 4 U ? + He
92 2Uranium-238 Alpha Particle
Note that the mass number always decreases by 4 after the alpha emission.
Atomic number decreases by 2
Alpha Radiation α
238 234 4 U Th + He
92 90 2Uranium-238 Thorium-234 Alpha Particle
Beta Radiation β 234 0 Th + e 90 -1
Thorium-234 Beta particle
By combining the charges from the bottom of the two symbols, figure out the symbol for the remaining particle
?
Beta Radiation β
234 234 0 Th Pa + e 90 91 -1Thorium-234 Beta particle
During the emission, a Thorium neutron becomes a proton and an electron. The electron is emitted as a beta particle.
Pa
Protactinium-234
Practice Problem• Give 2 examples of quantitative
data. Give 2 examples of qualitative data.
AnswersQuantitative data = how big, how
fast, how tall = measuredQualitative = relates to our 5 senses
– color, texture, odor, shape
Practice ProblemA small sphere has a mass of 2.5 grams. It has a density of 2.9 g/cm3. Determine the volume of the sphere.
Answer• 0.86 cm3
Review• How can we tell individual element
apart using a spectrometer?
Elements Emit only Specific Wavelengths
•Individual elements emit a spectrum containing discrete lines
•This is called a line spectrum
Review
Label each substance as a chemical change, physical change, chemical property, or physical property:
a. densityb. melting an ice cubec. reacts with oxygend. penny turns greene. dissolving sugarf. Colorg. Grilling a hamburger
Review
Label each substance as a chemical change, physical change, chemical property, or physical property:
a. density – physical propertyb. melting an ice cube – physical changec. reacts with oxygen – chemical propertyd. penny turns green – chemical changee. dissolving sugar – physical changef. Color – physical propertyg. Grilling a hamburger – chemical change
Review• Classify each of the following as:
elements (E), compounds (C),homogeneous mixtures (Hom), or heterogeneous mixtures (Het).
1.Copper 3. Lemonade2.Carbon dioxide 4. SaladThink of two other examples of each.
Answer
1.Copper - E2.Carbon dioxide - C3.Lemonade – Hom4.4. Salad – Het
Review• If electrons in an atom have the lowest
possible energy, the atom is in a state.
• If the electron absorbs energy from an outside source (heat, electrical current), the atom is in an state.
• How does this pertain to a flame test?
Answer• If electrons in an atom have the lowest
possible energy, the atom is in a ground state. • If the electron absorbs energy from an
outside source (heat, electrical current), the atom is in an excited state.
Review
• Identify the shape of each of the following molecules:
• (a) ammonia (NH3)
• (b) water (H2O)
Answer• (a) Pyramidal
• (b) Bent
Review• List radiation of the
electromagnetic (EM) spectrum from shortest to longest wavelength.
Answer
Gamma, x-rays, UV, visible light, IR, Microwave, radioVisible light = VIBGYOR