Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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using the periodic table provided, identify which of the following is t…
C. 87.62 amu; 38
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blocks on the periodic table will not list a(n): select the correct ans…
D. mass number
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6. what is the most likely ph for a solution of baking soda in distille…
A value greater than 7 (e.g., around 8.3)
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the noble gases are also called the: select the correct answer below: r…
B. inert gases
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what is responsible for ice floating in liquid water? a waters hydrogen…
d. all of the above
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elements in group 2 are: select the correct answer below: metalloids me…
B. metals
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the bonding responsible for the structure of ice is: a covalent bonding…
A. covalent bonding and hydrogen bonding
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the structure of ice is best characterized as: a a crystal lattice of a…
C. a hexagonally - shaped, open framework of molecules
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the hydrogen bonds in liquid water are ______ because water ______. a s…
B. short - lived; is a fluid
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the highest density of liquid water is at ______. a 100°c b 20°c c 0°c …
D. 4°C
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elements with the same number of electron shells are in the same: selec…
A. period
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the vertical columns of the periodic table are known as: select the cor…
C. groups
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using the periodic table provided, identify the symbol for nitrogen. se…
C. N
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a row on the periodic table is called a: select the correct answer belo…
period
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name e ifidro mejia 9/18/25 which of the following ground - state elect…
1. A. $1s^{2}2s^{1}$ 2. C. $1s^{2}2s^{2}2p^{6}$
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the reason that atomic numbers are always integer values is because eve…
a particular number of protons
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when discussing the periodic table, the word \group\ refers to: select …
a column
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2. dictionaries are reference books. that means they are sources that p…
B. The Encyclopedia of Chemistry
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which of the following does not belong to the noble gases? select the c…
potassium
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practice it! select the statement(s) that are accurate examples of phys…
Toasting marshmallows is a chemical change. Slicing carrots is a physical change. Decaying or rotting food is a chemical change.
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match the correct description to each model. not all answers will be us…
Without seeing the specific atom types in the models clearly, we can't give exact matches. But if all spheres are of one type in a model, it's an element. If different types of sp…
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cca 1 retest (8.6abe) 9 of 10 possible points: 7.09 alexandra and maddy…
Alexandra is correct because there is only one type of atom in each molecule.
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cca 1 retest (8.6abe) two solutions are mixed and react to produce the …
The mass remains constant.
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which element is not abbreviated based on an ancient name? select the c…
radium
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the table shows the chemical formulas for four substances. substance ch…
Substances 1 and 3
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the chemical symbol \cl\ with two capital letters is used to represent …
it is not a valid chemical symbol
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a chemical equation for the reaction between calcium hydroxide, and sul…
98 g
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an equation for a chemical reaction is shown. naoh + hcl -> nacl + h₂o …
Two hydrogen atoms are in the reactants, and two hydrogen atoms are in the products.
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which of the following actions would cause a chemical change? cracking …
frying an egg
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in the lab shown, a calcium chloride solution is mixed with a sodium su…
The Law of Conservation of Mass
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a student finds the ph of a sample of pond water to be 7.3. what does t…
E. It is slightly alkaline.
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the symbol fe could refer to which of the following? select the best an…
all of the above
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place the coefficients of each substance in their correct location. __c…
$2CH_4 ightleftharpoons1C_2H_2 + 3H_2$ (coefficients are 2, 1, 3)
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which is not a valid chemical symbol? select the correct answer below: …
A. Bp
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c4h10 + o2 → co2 + h2o how many molecules of o2 are needed to balance t…
C. 13
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practice it! which of the following is an example of a physical change?…
cutting the grass
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this is a model of a water molecule. element mass (u) hydrogen 1 oxygen…
C. All pure water samples include eight times the mass of oxygen than they do of hydrogen.
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what type of shapes did gauguin use most often? le orana maria paul gau…
D. organic
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what is a vitamin? any nutrient obtained in the diet that is required i…
an organic compound obtained in the diet that is required for normal metabolism
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use the graph to answer the questions. which part of the graph represen…
Which part of the graph represents activation energy? C. D Choose the best definition for activation energy: energy that must be added to start a reaction
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students in a chemistry class are using the periodic table to predict h…
C. $Li_2O$, E. ionic
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how many grams of sucrose (molecular weight = 342 g mole - 1) would you…
75.24 0.007524
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lab 4: q1 how many grams of nacl (molecular weight = 58.4 g mole-1) wou…
For Lab 4: Q1: 14.6 For Lab 4: Q2: 1.46
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activation energy is best defined as the energy that is transferred to …
is required for a chemical reaction to proceed.
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how did the concerns depicted in this cartoon affect the food industry?…
D. The federal government regulated the food industry in order to protect the health of the public.
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which three elements are found in every carbohydrate? sulfur phosphorus…
hydrogen, oxygen, carbon
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water can travel up a glass tube against the force of gravity! this is …
1. Cohesive 2. Adhesive 3. greater
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water molecules are also attracted to other kinds of molecules. this is…
cohesive, weaker, adhesive
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determine whether each statement is true or false. adhesive forces hold…
1. False 2. True 3. True 4. True 5. False
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2.1 the nature of matter chapter 2 study guide 1. the basic unit of mat…
1. Atom 2. Electron 3. C, H, Na 4. No 5. A substance made up of two or more different types of elements chemically combined in a fixed ratio.
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adhesive forces between water molecules and glass molecules help water …
- Water rises farther in a narrow glass tube than in a wide glass tube. - Water molecules are held together by hydrogen bonds as they rise in a capillary tube.
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methane burns in air according to this equation: ch₄(g) + 2o₂(g) → co₂(…
D. 144.0 g
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question 1 describe the difference between a chemical and an electrical…
**Question 1**: A chemical gradient is a concentration - based difference, while an electrical gradient is a charge - based difference across a membrane. **Question 2**: It is the…
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a scoop - shaped concave meniscus forms when adhesive forces between a …
Oil: Adhesive and cohesive forces are equal. Water: Adhesive forces are greater than cohesive forces. Mercury: Cohesive forces are greater than adhesive forces.
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7. use the word - bank to complete each sentence below. each word will …
1. Dependent Variable 2. Test Group 3. Hypothesis 4. Control Group 5. Independent Variable 6. Constant 7. A. True 8. A. True 9. B. False 10. A. True 11. B. False 12. A. True 13. B…
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which reaction type involves the exchange of ions between two compounds…
d. Double displacement
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10. jim looks at the periodic table of elements at a chemistry lab. he …
10. B. > 11. B. $0.12 12. C. 0.28 13. D. 0.94 14. A. 7
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water can form drops on a surface, like on a leaf. drops form because w…
- Cohesion is an attractive force between the same kinds of molecules. - The cohesive forces between water molecules are hydrogen bonds. - A water molecule can form hydrogen bonds…
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which reaction results in the formation of water? a. 2h₂o → 2h₂ + o₂ b.…
C. $2H_2 + O_2 ightarrow2H_2O$
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14. list 5 ways that water helps maintain homeostasis. 15. what propert…
1. Regulates body temperature through sweating. 2. Acts as a solvent for nutrient - waste transport. 3. Participates in chemical reactions. 4. Lubricates joints and tissues. 5. Ma…
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question 14 (5 points) if a scientist is studying the attraction of wat…
Question 14: B. Cohesion Question 15: A. This isn't considered a peer - reviewed paper because it wasn't reviewed by other scientists in the field.
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question 12 (5 points) listen regarding chemical elements such as argon…
Question 12: C. They don't react with other elements to form compounds. Question 13: C. zero population growth.
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question 7 (5 points) listen in which of the following cases does an at…
Question 7: A. There are more protons than electrons. Question 8: C. The atom determines the chemical property of an element.
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question 1 (5 points) listen why is water called the universal solvent?…
Question 1: A. Water can act as a solvent in many different solutions. Question 2: B. Trapping energy from the sun in the earth's atmosphere
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properties of water test review worksheet 1. what elements are importan…
1. Carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur 2. Covalent 3. Polar 4. Positively; negatively 5. Cohesion 6. Adhesion 7. Surface tension 8. Less density as a solid 9. N…
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10 question (2 points) 1st attempt part 1 (1 point) name the following …
Part 1: Carbon tetrachloride Part 2: Carbon monoxide
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09 question (2 points) 1st attempt part 1 (0.7 point) write the name of…
Part 1: Calcium chlorite Part 2: Iron(II) bromide Part 3: Dinitrogen tetrafluoride
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the metallic radius of an aluminum atom is 143 pm. what is the volume o…
$1.23\times 10^{-29}\ m^{3}$
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unit 1 test: nature of science 1. which of the following is not safe be…
1. B. Chewing gum during a dissection 2. A. Fire blanket 3. D. Science 4. B. Inference 5. C. A dirty pair of gloves 6. D. All of the above
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when a balloon does not pop during the skewer trick, what does this dem…
1. C. The strength and flexibility of polymers 2. a) Elasticity of the rubber molecules
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energy from the sun is changed into chemical energy by plants. coal con…
B. Energy from the Sun is changed into chemical energy by plants.
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place the coefficients into the underlined spaces to balance the chemic…
2, 1, 2, 1
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find the ph of a solution containing 0.45 m of the strong base naoh. 0.…
13.65
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what type of compound is formed from a base accepting an h+ ion? conjug…
D. Conjugate acid
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an acid exhibits a 3.2% ionization. is this a strong or weak acid? stro…
B. Weak acid! The acid doesn't completely dissociate.
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find the poh of a solution containing 0.45 m of the strong base naoh. 1…
C. 0.35
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calculate the percent ionization of a weak acid with a concentration of…
$2.6\%$ (corresponding to the first option in the multiple - choice list)
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2nd attempt part 1 (0.3 point) give the name of hf (include the word ac…
- Part 1: hydrofluoric acid - Part 2: nitric acid - Part 3: \(H_3PO_4\)
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part 3 (0.3 point) give the chemical formula of phosphoric acid; part 4…
Part 3: $H_3PO_4$ Part 4: $HNO_2$
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7. a picture of a cat is briefly flashed in the left visual field and a…
7. D. right hand to indicate she saw a mouse 8. B. false
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move the reactants into the synthesis reaction. balanced synthesis reac…
The first blank is \(NH_3\), the second blank is \(H_2SO_4\).
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question 1 explain how a water strider can float on the surface of wate…
Question 1: Water striders float due to water's surface tension and their hydrophobic legs. Question 2: Water is polar and can dissolve many substances. Question 3: Ionic bonds in…
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what volume is indicated on each of these graduated cylinders? the unit…
a) 56.5 mL b) 4.2 mL c) 24 mL d) 17 mL e) 77 mL f) 4.7 mL
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question 11 of 22 > determine the formula unit for the compound formed …
$AlCl_{3}$
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14 question (3 points) an neutral atom has 60 electrons and a mass numb…
Part 1: 60 Part 2: 83 Part 3: $_{60}^{143}Nd$
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part 3 (0.5 point) lithium combined with nitrogen is... formula: name: …
Part 3: formula: $Li_3N$ name: lithium nitride Part 4: formula: $AlCl_3$ name: aluminum chloride
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roberto examines two molecular models. he sees that the atoms are the s…
two geometric isomers that have the same molecular formula
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how many covalent bonds can a typical carbon atom form? one two three f…
D. four
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gina wants to use models to better understand how the types of bonds in…
the ball-and-stick model
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which of the following represents an organic compound?
The third structure (the one with carbon - carbon double bond and carbon - hydrogen bonds) represents an organic compound.
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part 1 (0.5 point) potassium combined with bromine is... formula: name:…
Part 1: formula: $KBr$ name: potassium bromide Part 2: formula: $CaH_2$ name: calcium hydride
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which statement best describes why carbon can form a wide variety of or…
Each carbon atom covalently bonds with atoms of carbon, hydrogen, oxygen, and nitrogen.
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a student states that this structural formula represents a hydrocarbon.…
C. No, a hydrocarbon contains only carbon and hydrogen atoms.
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sort each of the following binary compounds into the correct category b…
Ionic: CsBr, Li₂O, Al₂O₃, NaCl Covalent: NO₂, CCl₄, SO₃
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what is a disadvantage of using a structural model to show a chemical c…
Structural models provide minimal three - dimensional information.
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how many isomers does hexane (c6h14) have? o four o five o six o seven
B. five
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which of the following best explains why a structural formula of a chem…
Both formulas identify the specific atoms in a particular compound. However, a structural formula also shows how the atoms in a compound are bonded together.
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part 3 (0.7 point) n₂o₃ choose one or more: □ nitrogen is the cation. □…
D. Oxygen is the anion. E. It would be named as a molecular compound.
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structural isomers are chemical compounds that have the same atoms that…
The same atoms that are arranged in different orders.
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choose one or more: calcium is the cation. calcium is the anion. phosph…
For the first part: Calcium is the cation., Phosphate is the polyatomic anion. For the second part: Oxygen is the anion., It would be named as a molecular compound.