Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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question select all the correct answers. which actions show that mixing…
purifying water with a carbon filter, a soda fizzing when its cap is opened, a metal mixed with a very small amount of a nonmetal to make a metallic alloy
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question select all the correct answers. which observations show that a…
B. Overnight, dew forms on the grass.
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gain two electrons are found in group two atoms will be positive ions i…
A. Alkaline earth metals do not gain two electrons, they lose two electrons.
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what defines a mixture? a. can be broken down into its basic parts thro…
A. can be broken down into its basic parts through physical means
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question select the correct answer. a scientist compares two samples of…
Density calculations show that the gases are different, so a chemical reaction occurred.
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which ion has a charge of 2+? a. an ion with 10 protons, 10 neutrons, a…
B. an ion with 10 protons, 9 neutrons, and 8 electrons
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question select all the correct answers. which of these events indicate…
Silver jewelry becomes dark because of tarnish., A solid appears when two water-based solutions are added together.
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which of the following interactions results in a new substance? i. when…
A. II and III only
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pure copper metal has a very high conductivity. brass, an alloy of copp…
A. because the physical properties of the mixture are different than its components
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which of the following is formed when two or more different kinds of at…
B. compound
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lisa had an unknown clear liquid in a beaker. after heating on a hot pl…
A. a mixture
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sewage treatment plants use settling tanks to separate raw sewage into …
C. heterogeneous
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how can damage to living things occur from exposure to x - rays or gamm…
A. Atoms and molecules in the body can be ionized.
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the periodic table organizes the 118 known chemical elements. which pro…
A. atomic number, which is equal to the number of protons in an atom
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question type your response in the box. a reddish layer of rust can for…
Reactants: Iron and Oxygen; Product: Iron Oxide. Word equation: Iron + Oxygen react to form Iron Oxide.
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which option best describes electromagnetic waves that have enough ener…
C. Ionizing radiation
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a shiny substance that conducts electricity in its solid state is most …
C. a metallic element.
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what physical property could be used to easily separate a mixture of sa…
D. solubility
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hydrogen has been placed at the top of the first column of the periodic…
B. one valence electron
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which of the following substances is an element? a. water (h₂o) b. carb…
B. carbon (C)
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which of these elements is the least reactive? a. sodium b. krypton c. …
B. krypton
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most of the volume of an atom is occupied by the a. nucleus. b. nuclide…
C. electron cloud
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atoms in period three and beyond can expand their in a lewis dot struct…
octet
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a molecule of saturated triacylglycerol (also known as triglyceride) co…
The maximum number of hydrogen atoms in the fatty acid chain.
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why do noble gases typically not react with other elements chemically? …
C. because they have a full outer shell of valence electrons
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the molecule water (h₂o) has a shape in its lewis dot structure.
bent
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which three elements have the most similar chemical properties? a. o, n…
B. K, Rb, Cs
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the isotope einsteinium - 252 has a half - life of 472 days. after a to…
20. 612
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it is important to study the __________ of a material to identify the p…
C. Reactivity
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lone pairs in a lewis dot structure are non - bonding pairs of
electrons
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using the periodic table, classify these elements as metals, nonmetals,…
Si: metalloid; He: non - metal; Fe: metal; K: metal
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using the periodic table, classify these elements as metals, nonmetals,…
B. Si = metalloid, He = nonmetal, Fe = metal, K = metal
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using the periodic table, classify these elements as metals, nonmetals,…
B. Si = metalloid, He = nonmetal, Fe = metal, K = metal
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ph, acids and bases quick check how are acids and protons related? (1 p…
An acid can donate protons to a base when they react.
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the elements in group 17 of the periodic table are all called halogens.…
D. number of valence electrons
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conductivity: none malleability: brittle this unknown substance is most…
C. a metalloid
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atom a and atom b have the same number of protons, but they do not have…
Atom A and Atom B are isotopes of the same element.
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conductivity: none malleability: brittle this unknown substance is most…
C. a nonmetal
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ph, acids and bases quick check which statement best describes the diff…
The substance with a pH of 3.0 has 1,000 times as many hydrogen ions per volume of water as the substance with a pH of 6.0.
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ph, acids and bases quick check. use the reaction to answer the questio…
$HCl$ is an acid, and $Cl^-$ is its conjugate base.
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joelle is a manager at a construction company, and she is interested in…
$\ce{C_{27}H_{36}N_{2}O_{10}}$
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ph, acids and bases quick check which pattern in electronegativity do e…
Electronegativity increases from left to right within a row of the periodic table.
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which element is most likely to be shiny? sulfur (s) boron (b) calcium …
C. calcium (Ca)
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this is how sodium appears in the periodic table. the arrow is pointing…
atomic mass
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ph, acids and bases quick check which option correctly shows the concen…
A. $1.0\times 10^{-7}\text{ mol/L}$
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the table shows the physical properties of an unknown substance after i…
Neither A. a metal nor B. an alloy.
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which best describes a radioactive isotope? o an atom is unstable. o an…
An atom is unstable.
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which of the following is true with regard to sodium and potassium? a. …
D. They tend to form cations.
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what did rutherfords model of the atom include that thomsons model did …
A. a nucleus
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to achieve a complete set of valence electrons, atoms must fulfill the …
C. share, gain, or lose electrons
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which determines the reactivity of an alkali metal? its boiling and mel…
D. its ability to lose electrons
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*solids at room temperature *forms positive ions *good conductors of el…
Na
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what trend does the reactivity of most nonmetals show in a periodic tab…
C. increases from left to right across the periodic table
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cecil is working with samples of chlorine (cl), oxygen (o), bromine (br…
silver
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a group of elements have the following properties. +solids at room temp…
A metal element (e.g., iron, copper)
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the table below lists the properties of a metallic element. where on th…
Group 12
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reading the element individual tiles element name silver 47 atomic numb…
Find the chemical symbols for these elements: Gold: Au Fluorine: F Sulfur: S Find the names for these elements: Mg: Magnesium N: Nitrogen He: Helium Find the atomic numbers for th…
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this chart show the amount of radioactivity measured from three unknown…
Isotope A was measured at day 24, Isotope B was measured at day 6, and Isotope C was measured at day 10.
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while looking at xenon (xe) on the periodic table, a student needs to f…
A. directly up
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what are the two parts of an atom? the nucleus and the proton cloud the…
the nucleus and the electron cloud
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an atom of the element zinc has an atomic number of 30 and a mass numbe…
A. 30
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8 multiple choice 1 point find the symbol for the element with 13 proto…
8. ²⁷Al 9. gamma 10. alpha 11. rhodium - 104
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when an atom that has no charge loses two electrons, it becomes a posit…
A. positive ion
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1. water is a(n) ______________. (select all that apply.) a. pure subst…
A. pure substance D. compound
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who described atoms as small spheres that could not be divided into any…
B. Dalton
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fill in the blank question chemicals classified as either vasodilators …
pharmacologic
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which argument best explains the charge of an atomic nucleus? an atomic…
An atomic nucleus is positively charged because it is composed of protons.
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which lists only metalloids? arsenic (as), sulfur (s), and polonium (po…
C. boron (B), germanium (Ge), and tellurium (Te)
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2. what percent of earths water is freshwater? only 3% of earths water …
2. 3% of Earth's water is freshwater. 3. Polarity is a molecule having slightly positive and negative parts; water is polar (oxygen slightly negative, hydrogens slightly positive)…
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introductions quick check what is the best definition of strategy? (1 p…
a plan for achieving something
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which properties make a metal a good material to use for electrical wir…
B. conductivity and ductility
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who is known as the \father of modern chemistry\ because he first organ…
B. Antoine Lavoisier
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which lists the elements in order from most conductive to least conduct…
D. potassium (K), germanium (Ge), selenium (Se)
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4 multiple choice 1 point which of the following is not a type of elect…
4. B. mechanical waves 5. C. Protons 66, Neutrons 92 6. A. Protons 16, Neutrons 18 7. D. $^{159}$Tb
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5 matching 4 points match the following matter mixture elements compoun…
Matter - Something that has mass and occupies space Mixture - Mixture of substances Elements - Substance composed of only one type of element Compound - Substance composed of 2 or…
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which statement best describes the rhyme schemes of \the author to her …
Bradstreet uses couplets for their overall rhyme scheme and structure; Wheatley uses couplets to enhance the poem as a song of praise for creation.
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part 3: vocabulary word bank — match the word to its correct definition…
Isotopes - b) Atoms of the same element with different numbers of neutrons. Average atomic mass - a) The weighted average mass of all naturally occurring isotopes of an element. M…
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17. what is the maximum number of electrons in the first energy level? …
17. a) 2 18. b) A horizontal row 19. b) Nonmetals 20. b) They have no charge 21. True 22. False 23. True 24. False 25. False
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read the passage. from return of the native the scene was strangely hom…
4. No, because the figure remains inseparable from the structure as a whole until she moves, implying that the word means "motionlessness."
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9. isotopes are atoms of the same element that have: a) different numbe…
9. b) Different numbers of neutrons 10. b) Atomic number 11. c) Electron 12. b) The weighted average of all isotopes 13. b) The area where electrons are likely to be found 14. a) …
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part 1: subatomic particles complete the following chart: (1 point each…
| PARTICLE | CHARGE | MASS | LOCATION IN ATOM | | ---- | ---- | ---- | ---- | | proton | + 1 | ~1 amu | núcleo | | neutron | 0 | ~1 amu | núcleo | | electron | - 1 | ~$\frac{1}{18…
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investigate 3. use the menu on the right - side of the program to selec…
4. Without the Celsius value, we can't give an exact answer. But if at freezing - point of water ($0^{\circ}C$), it is $273.15\ K$. 5. The ice melts and turns into liquid water. 6…
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part 1: multiple choice (abc) — choose the correct answer 1. which suba…
1. b) Proton 2. b) Negative 3. b) Atomic number 4. b) Nucleus 5. a) To organize elements by atomic number 6. a) Subatomic particles that make up protons and neutrons 7. c) Electro…
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which element is not placed in one specific group because of its unique…
hydrogen
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all metals share the exact same chemical and physical properties. true …
False
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hydrogen is generally not placed in a specific group. true false
True
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which is not a specific classification group of metals? metalloids the …
A. metalloids
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non - metals are poor conductors of heat or electricity. o true o false
True
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part 3: which element am i? write the element name & symbol described b…
1. Litio (Li) 2. Magnesio (Mg) 3. Plomo (Pb) 4. Azufre (S) 5. Titanio (Ti) 6. Zirconio (Zr) 7. Hidrógeno (H) 8. Hierro (Fe) 9. Plata (Ag) 10. Yodo (I) 11. Plutonio (Pu) 12. Cobre …
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according to the gas laws, what might be a possible outcome if you left…
B. H₂O will increase in volume when transitioning from a liquid to solid state. This will cause the bottle to explode.
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match the equipment to its use. write the letter. 1. ___ protects your …
1. a. Safety goggles 2. d. Eyewash Station 3. b. Lab Gown 4. c. Fire Extinguisher 1. Follow all instructions carefully. This helps prevent accidents and ensures safety in the lab.
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fill in the blanks: 7. what is our universal address (where are we in t…
Solar System; Milky Way; House of Linnaeus
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part 1: multiple choice: circle the letter of the correct answer. 1. wh…
1. b) Safety goggles 2. b) Tell the teacher immediately 3. b) Eating food during an experiment 4. b) Putting out small fires 5. c) Tell the teacher and use a broom/dustpan
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this exam is closed - book. before starting, make sure you have studied…
C. After 5 to 7 days
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question 28 2 pts which of the following would not reasonably pose a ri…
The client's hair
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2 classify the characteristics of endothermic and exothermic correctly.…
Endothermic: Energy is ABSORBED from the surroundings, Products have MORE energy, Products feel COLDER Exothermic: Energy is RELEASED to the surroundings, Products have LESS energ…
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write the chemical formula for the ionic compound provided. 11. calcium…
11. $CaF_{2}$ 12. $MgO$ 13. $Na_{3}N$ 14. $K_{2}S$ 15. Aluminum oxide 16. Sodium chloride 17. Barium chloride 18. Calcium oxide 19. Strontium oxide 20. metals; non - metals; non -…
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which of the following is an example of cultural diffusion? a new volca…
1. C. The spread of sushi from Japan to the United States 2. C. Cold with long winters and short summers 3. Physical weathering (not given as an option in the visible part of ques…
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bonding - naming ionic compounds name: kimora bright period: 4th 1. how…
1. C. It loses 3 electrons 2. C. 2 3. A. Covalent bond 4. D. Ca and Br 5. C. Br 6. B. - 2 7. D. CO₂ 8. A. Sodium has a positive charge and chlorine has a negative charge 9. positi…
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model 3 - boiling points of alcohols alcohol\tformula\tnumber of carbon…
a. The number of carbon atoms in the alcohol molecules. b. The boiling point of the alcohol. c. The volume of alcohol and room pressure.