Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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3. explain the difference between the mass of a proton and the mass of …
The nucleus contains protons and neutrons which are much more massive than electrons, so it is responsible for nearly all of the atom's mass. A proton is much more massive than an…
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8. the tendency for water molecules to be attracted and stick to other …
8. Adhesion 9. a. It helps some insects "skate" across the surface of the water. b. It refers to the tightness across the surface of the water. d. It causes raindrops to form roun…
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example problem: the following initial rates were measured for the reac…
(a) Rate law: rate = $k[X][Y]$, Overall order = 2 (b) $k = 0.40\ M^{-1}s^{-1}$ (c) $0.036\ M\ s^{-1}$ (d) $0.0625\ s$
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9) brass is an alloy of copper (cu) and zinc (zn). if 8.32 g of copper …
A. $1.10\times 10^{23}$ metal atoms
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3. explain why there are different branches of chemistry 4. explain why…
3. Chemistry is vast and different branches focus on specific aspects for in - depth study. 4. Mass is constant while weight can vary, so mass is preferred for consistent measurem…
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the electronic structures of some atoms and ions are shown. (a) write t…
(a)(i) A, F (ii) B (iii) D (b)(i) $H^-$ (ii) $Al$
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properties of water write the definition of each key term. polarity: co…
- Polarity: Uneven charge distribution in a molecule. - Cohesion: Attraction between like molecules. - Adhesion: Attraction between unlike molecules. - Capillary action: Movement …
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1 what is chemistry? (continued) check your progress 1. explain why the…
1. Chemistry helps understand matter and impacts daily life in multiple areas. 2. A substance is matter with definite composition and properties. Examples: water, sodium chloride.…
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the motion of the particles. 4 8. this question is about zinc and compo…
(a) Good electrical conductivity, High thermal conductivity, Malleability 9. (a) (i) A, H (ii) B (iii) D
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which of the following relates the impact of rachel carsons silent spri…
The question is not clear as the text is blurry and some parts seem to be cut - off. Please provide a clear and complete question.
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(b) group i elements have lower melting - points than transition elemen…
(b) Group I elements are softer. (c) Solid (d)(i) original colour of potassium bromide solution: Colourless; final colour of reaction mixture: Orange - brown 7.(a) A: Freezing; B:…
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which statement is true regarding a chemical reaction? (1 point) the to…
The total number of atoms does not change, so mass is conserved in the reaction.
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in which chemical equation is the number of atoms in the reactants the …
$\text{Zn}+2\text{HCl} ightarrow\text{H}_2+\text{ZnCl}_2$
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conservation in chemical reactions quick check which of the following e…
# Explanation: ## Step1: Recall the Law of Conservation[SSE Completed, Client Connection Error][SSE Completed, Client Connection Error][LLM SSE On Failure]
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elements j and k are in the same period in the periodic table. j reacts…
D. J is to the left of K in the Periodic Table. ### 6. (a) (i)
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conservation in chemical reactions quick check which of the following e…
None of the above. The balanced equation that demonstrates the Law of Conservation of Mass for the[SSE Completed, Client Connection Error][SSE Completed, Client Connection Error][…
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parts of a reaction use the following reaction to answer the question t…
products
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real-world connection analyze the importance of chemistry in our societ…
Chemistry is highly important in society as its branches contribute to materials science, medicine, quality - control, and biotechnology among other areas.
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parts of a reaction what part of a chemical reaction is highlighted in …
states of matter
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1. which statement describes the particles in a liquid? a they are clos…
1. A. They are close together but have no regular arrangement. 2. B. carbon monoxide and nitrogen 3. B. Elements are arranged in order of increasing proton number.
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1 what is chemistry? (continued) get it? identify two additional types …
1. Mathematical models, Computer - simulated models 2. Applied research 3. 1. Water 2. Salt 3. Sugar 4. Vinegar 5. Baking soda 6. Ethanol
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8. find the mass to prepare a 1m solution of kcl (potassium chloride) i…
: ## 8. 0.7455 g ## 9. a. 3000 μL; 0.45 mL b. 2500 mg; 3500 μg # Explanation: ## 8. ## Step1: Calculate moles of KCl Use formula $n = M\times V$. Given $M = 1M$ and $V=10\ mL=0.01…
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8. find the mass to prepare a 1m solution of kcl (potassium chloride) i…
: 8. 0.7455 g 9. a. 3000 μL; 0.45 mL b. 2500 mg; 3500 μg # Explanation: ## Step1: Calculate moles of KCl in 8 Use molarity formula $n = M\times V$. Given $M = 1M$, $V=10\ mL=0.01\…
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what part of a chemical reaction is highlighted in red? reactants produ…
Products
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which process is a sign of a chemical change? a cloud quickly changes s…
A rotting potato gives off a bad smell
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physical or chemical change? breaking a glass bottle. chemical physical
Physical
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which is a nonpoint source of pollution? tourists throw trash into the …
Rain contains chemicals that seep into the ground.
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physical or chemical change? digestion of food.
Both
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physical or chemical change? cutting your hair.
Physical
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use the following reaction to answer the question to the right. cl₂(aq)…
products
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physical or chemical change? copper tarnishing. chemical physical
Chemical
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matter is anything that has. atoms are the and. the smallest unit of ma…
# Explicación: ## Paso 1: Identificar propiedades de partículas subatómicas Los protones tienen una carga positiva (+1), una masa de aproximadamente 1 amu y se encuentran en el nú…
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physical or chemical change? evaporation. physical chemical
Physical
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which one stays the same during physical and chemical changes? shape ar…
Mass
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which one is not a sign of chemical change? change of odor change of co…
change of shape
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baking a cake is physical change chemical change
chemical change
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painting a fence is _ physical change chemical change
physical change
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fireworks are physical change chemical change
chemical change
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11 use the periodic table. match each statement with the proper classif…
| Statement | Metals | Nonmetals | |--|--|--| | contains many solids | $\checkmark$ | | | conducts electricity in the solid state | $\checkmark$ | | | tends to gain electrons and …
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ic 25 - 26 american literature 1 make it new!: early modernism night by…
# Breve explicación: Al examinar los dos poemas, "Night" no sigue un patrón rítmico específico como el trocaico pentámetro, tampoco tiene un esquema de rima evidente. "Roses" tamp…
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cooking scrambled eggs is _ chemical change physical change
chemical change
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temperature rises when magnesium puts into an acid solution is physical…
chemical change
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temperature drops around dry ice (solid co₂) is chemical change physica…
physical change
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putting magnesium into an acid solution and producing a lot of gas is
A chemical change
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boiling water producing a lot of bubbles is _ physical change chemical …
physical change
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dry ice (solid co₂) at room temperature produces lots of gas is ___. ch…
physical change
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iron and sulfur mix and turn to a black and yellow mixture is _ chemica…
physical change
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letting the apple sit out and it turns brown is ___. chemical change ph…
chemical change
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cutting an avocado in half is physical change chemical change
physical change
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mixing two clear solutions that turned cloudy white is physical change …
chemical change
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hammering a nail into a piece of wood is____ physical change chemical c…
physical change
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identifying resources impacted by human activity oil is a fossil fuel u…
A. air C. water F. organisms in water
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letting the nail rust is____ chemical change physical change
chemical change
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1) determine the theoretical yield (in g) of hcl if 65.0 g of bcl₃ and …
C. $55.6\ g\ HCl$
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burning a piece of paper is chemical change physical change
chemical change
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tearing a piece of paper into 100 pieces is physical change chemical ch…
Physical change
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fill in the blank question the basic unit of carbohydrates is a monosac…
One; Sugar
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select the statement that explains how the reaction rate is affected if…
The reaction rate decreases.
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name sarah harrison 11:30am. october 1, 2025 exam 3 1. you can hold a m…
1. D. Reciting, in your own words, what you have just read. 2. True 3. False 4. C. Unabridged 5. False 6. D. To create signals for later review sessions. 7. False 8. True 9. B. Re…
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4 which pair of arrows correctly represents how the atomic radius of el…
The pair of arrows that shows one arrow pointing downwards (to represent increase in atomic radius down a group) and one arrow pointing to the left (to represent increase in atomi…
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4 which pair of arrows correctly represents how the atomic radius of el…
# Explanation: ## Step1: Recall atomic - radius trends Atomic radius[SSE Completed, Client Connection Error][SSE Completed, Client Connection Error][LLM SSE On Failure]
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3 why is the electronegativity value of most noble gases equal to zero?…
A. They don't attract electrons; they are already stable with a full valence shell.
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3 why is the electronegativity value of most noble gases equal to zero?…
# Brief[SSE Completed, Client Connection Error][SSE Completed, Client Connection Error][LLM SSE On Failure]
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3 why is the electronegativity value of most noble gases equal to zero?…
# Brief[SSE Completed, Client Connection Error][SSE Completed, Client Connection Error][LLM SSE On Failure]
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2 the trend for electronegativity as you travel down the column is decr…
B. True
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classify the following as either metals or non - metals by dragging the…
Metals: magnesium, sodium, iron, gold Non - Metals: xenon, iodine, sulfur, helium, oxygen
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13) using the actual molarity of the naoh solution, calculate the molar…
\(M_{H_3PO_4}=0.4167M_{NaOH}\)
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agriculture has no impact on the levels of organic content in soil beca…
F
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9. explain using a formula to show the difference between these 4 react…
| Reaction Type | Generic Formula | Example | |--|--|--| | Formation | A + B → AB | 2H₂ + O₂ → 2H₂O | | Decomposition | AB → A + B | 2H₂O → 2H₂ + O₂ | | Single Substitution | A + …
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7. convert the following word equations into chemical formulas (skeleto…
1. $3Ca + N_{2} ightarrow Ca_{3}N_{2}$ 2. $MgI_{2} ightarrow Mg + I_{2}$ 3. $CuCl_{2}+MgBr_{2} ightarrow CuBr_{2}+MgCl_{2}$ 4. Increase temperature, increase concentration of reac…
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c₂h₆(g) + o₂(g) → express your answer as a chemical equation. identify …
$2\mathrm{C_2H_6(g)} + 7\mathrm{O_2(g)} ightarrow4\mathrm{CO_2(g)}+6\mathrm{H_2O(l)}$
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part d bacl₂(aq) + h₃po₄(aq) → ba₃(po₄)₂(s) + hcl(aq) express your answ…
3,2,1,6
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2 what is a diatomic molecule? include 3 of the \special seven\ diatomi…
A diatomic molecule is a molecule composed of two atoms. Three of the "special seven" diatomic elements are hydrogen (H₂), oxygen (O₂), and nitrogen (N₂).
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1 what is chemistry? (continued) compare and contrast mass and weight u…
Mass circle: "a measurement that reflects the amount of matter in an object", "does not reflect gravitational pull on matter"; Weight circle: "a measure of the effect of gravitati…
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short answer. explain the rules used when naming the following types of…
1. A diatomic molecule is a molecule made up of two atoms. Example: Oxygen gas exists as O₂. Rules for naming molecular compounds: Use prefixes to denote the number of atoms of ea…
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3. identify the following components of a chemical reaction. h2 + o2 → …
Reactants: $H_2$, $O_2$; Product: $H_2O$
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na₂s(aq) + cu(no₃)₂(aq) → nano₃(aq) + cus(s) express your answers as in…
1,1,2,1
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11. each column or group in the periodic table is called a family. elem…
Alkali Metals - 1 valence electron: Sodium (Na), Lithium (Li) Alkaline Earth Metals - 2 valence electrons: Calcium (Ca), Barium (Ba) Boron Family - 3 valence electrons: Boron (B),…
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when researching a topic, a student has taken the following notes: - in…
D. Kat's approach substitutes a natural, plant - based substance for the hazardous chemicals that manufacturers have traditionally used.
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the average atomic mass is equal to the number of neutrons in an atom. …
1. B. False 2. A. True
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core - question # 8 hcfc refrigerants contain which of the following? a…
C. Hydrogen, chlorine, fluorine & carbon
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which of the following atomic particles is positively charged? * neutro…
1. proton 2. True
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nitrogen monoxide gas reacts with hydrogen gas to form ammonia gas and …
$2NO(g)+5H_2(g) ightarrow 2NH_3(g)+2H_2O(g)$
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atoms consist of a positively charged center called a(n) ____________.*…
1. D. nucleus 2. B. electrons
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elements in group 2 are all called alkaline earth metals. what is most …
which chemical properties they have
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this is how fluorine appears in the periodic table. which is one piece …
the atomic number
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multiple - choice question the soil in forested wetlands has dark soil,…
B. organic matter
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in an elements square on the periodic table, the number with the greate…
atomic mass.
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how do we know this fireworks display is a chemical change? there is an…
There is an increase in heat.
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unit 1 combustion write 5 things you already know about combustion: 1. …
1. Combustion is a chemical reaction. 2. It needs fuel, oxygen, and heat. 3. Fire produces heat and light. 4. Combustion can be rapid or slow. 5. Some materials are combustible, o…
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when wood is burned, which of the following indicates that a chemical c…
change in color
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this is how zirconium appears in the periodic table. rounded to the nea…
40
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which of the following choices is an example of a chemical change? a ru…
a rusty car
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what are 1a, 3b, and 7a examples of on the periodic table? groups. numb…
groups.
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which of the following is an example of a chemical change? ice cream wi…
burnt toast
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which of the following is a sign of a chemical change? new color new sh…
new color
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this is how krypton appears in the periodic table: rounded to the neare…
36
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facts about five elements element atomic mass (amu) total electrons val…
Aluminum, boron, and gallium are likely together in one group because they have the same number of valence electrons, and carbon and germanium are likely together in another group…
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based on the information in the table, which elements are most likely i…
None of the options are correct as the criteria used in each option (atomic mass, year of isolation, element name ending) are not valid for determining elements in the same period…
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which two chemists organized elements based on properties such as how t…
B. Döbereiner and Newlands