Chimie
Réactions chimiques, stœchiométrie, structures moléculaires et propriétés.
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8. when you add the electrons in each energy level, the sum represents …
1. electrons 2. protons 3. atomic number ### Question 9
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an electron in an atom is in the n=2 and l=1 quantum level. part 1 of 2…
\( 0, 1 \) ### Part 2 of 2
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4. aluminum has how many electrons?
13
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fast focus standard 3a / page 5 1 a chemist poured formaldehyde into th…
A ### Page 5 Question 2
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consider the bohr model of an atom. part 1 of 2 complete the following …
emitted ### Part 2 of 2 For the transition from \(n = 7\) to \(n=2\):
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7. how many electrons does aluminum have in the first energy level?
2
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determine the reaction mass efficiency for the reaction below, given th…
0.0509
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determine the reaction mass efficiency for the reaction below, given th…
The reaction mass efficiency is approximately \( 4.57\% \)
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4. what happens in a chemical reaction? a) new elements are created. b)…
b) The atoms of reactants rearrange to form new products. ### Question 5
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a type of radiation has an energy of 4.70 × 10⁻²² kj. note: reference t…
\(423\space nm\)
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directions: read each question carefully and answer by choosing the cor…
a) Proton, Electron, Neutron ### Question 2
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how many sig figs are in this number 1 g = 1000 mg 1 3 4 infinite
infinite
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how many sig figs are there in each number 2.5010 2.501 0.025 0.002 0.0…
s: - 2.5010: $\boldsymbol{5}$ - 2.501: $\boldsymbol{4}$ - 0.025: $\boldsymbol{2}$ - 0.002: $\boldsymbol{1}$ - 0.0250: $\boldsymbol{3}$
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density of a liquid was found to be 1.05 g / cm^3, what will be the den…
8.7318 lb/G
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22. the elements c, be, na, mg, ne, o listed in order of increasing fir…
E. Na, Mg, Be, C, O, Ne
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question 3 of 5 why does working out make us feel good? a. it releases …
D. All of the above.
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▲1-70 assign each of the following descriptions of matter to one of the…
s: a. mixture b. compound c. compound d. mixture
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▲1-68 in the following diagrams, different colored spheres represent at…
III, IV b. # Brief Explanations: A mixture has two or more substances. Diagrams I (two elements) and II (two elements + compound, but considered as two substances) are mixtures.
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21. which of the following atoms has the largest radius? a. na b. c c. …
C. Ba
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a(n) of carbon dioxide contains one carbon atom and two oxygen atoms.
molecule
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1-66 indicate whether each of the following statements is true or false…
False. Rewrite: A molecule of an element is always homoatomic (contains only one type of atom), while heteroatomic molecules are characteristic of compounds (containing different …
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1-64 assign each of the following molecular descriptions for a pure sub…
(2) must be a compound ### Part b
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20. in general, as you go across a period from left to right in the per…
D. decreases, increases, increases
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15. which of the following combinations of quantum numbers is permissib…
C. \( n = 3, l = 2, m_l = 1, m_s = +\frac{1}{2} \)
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18. what is the electron configuration for an iodine atom? a. kr5s²4d¹⁰…
A. \([Kr]5s^24d^{10}5p^5\)
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portions of orbital diagrams representing the ground-state electron con…
The orbital diagram with $\boxed{11\ 1\downarrow\ 1\ 1\ 1}$ (the third one) violates the Pauli exclusion principle.
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1-58 classify the substances represented by the following models as hom…
a. Heteroatomic b. Homoatomic c. Heteroatomic d. Heteroatomic
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the electron configurations described in this chapter all refer to gase…
$1s^{2}2s^{2}2p^{2}3d^{1}$ (the second option: $1s^{2}2s^{2}2p^{2}3d^{1}$)
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what is the maximum number of electrons that can have n=4, m_l=-1 in an…
6
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1-56 in which of the following sequences of elements do all the element…
a. Silver, gold, mercury
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in the series shown below, which of the following has the most unpaired…
P (with 3 unpaired electrons)
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give the electron configuration for the element given. use the noble ga…
\( [\text{Ar}] 4s^2 3d^{10} 4p^2 \)
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7. how are the terms group period used on the periodic table?
- **Group**: Vertical columns in the periodic table. Elements in the same group have the same number of valence electrons, resulting in similar chemical properties. - **Period**: …
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1-56 in which of the following sequences of elements do all the element…
d. Potassium, iron, lead
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write the ground-state electron configuration for each element. part 1 …
s - Au: $\boldsymbol{[Xe]4f^{14}5d^{10}6s^{1}}$ - As: $\boldsymbol{[Ar]4s^{2}3d^{10}4p^{3}}$
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8. what is the general location of metals on the periodic table?
Metals are generally located to the left of the zig - zag (staircase) line that separates metals, non - metals, and metalloids on the periodic table. In general terms, they are fo…
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1-54 write the chemical symbol for each member of the following pairs o…
Copper: Cu; Cobalt: Co ### Part b
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1-52 give the chemical symbol for each of the following elements. a. me…
a. Mercury: Hg b. Chlorine: Cl c. Gold: Au d. Beryllium: Be
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6. what three metals are in the third period (row) of the periodic tabl…
Sodium (Na), Magnesium (Mg), and Aluminum (Al)
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5. the elements fluorine, chlorine and bromine are in which group of th…
c. the halogens
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1. groups of the periodic table corresponds to elements with: a. the sa…
c. Similar chemical properties
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1-50 give the name of the element denoted by each of the following chem…
a. Lithium b. Helium c. Fluorine d. Zinc
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complete this equation that represents the process of nuclear fission. …
A: \(146\) B: \(56\)
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1-48 with the help of figure 1-10, indicate whether the first listed el…
s: a. More abundant (Oxygen vs Hydrogen) b. Less abundant (Iron vs Aluminum) c. Less abundant (Calcium vs Magnesium) d. Less abundant (Copper vs Sodium)
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choose the total number of each item requested below. 4c₆h₁₂o₆ carbon a…
Carbon atoms: 24 Hydrogen atoms: 48 Oxygen atoms: 24 Molecules: 4
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1-46 indicate whether each of the following statements about elemental …
False ### Part b
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which orbital is lower in energy in a many-electron atom? ○ 3s ○ 4s
\(3s\) (i.e., the option with "3s")
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indicate the total number of 4d electrons in ba (z=56).
10
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elija tres pasos que garanticen la seguridad del laboratorio durante el…
- Usando pinzas para manipular los tubos de ensayo calientes - Apagar la placa calefactora después de usarla - Comprobación de que el vaso de precipitados no tenga virutas antes d…
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laboratorio: identificación de nutrientes asegúrese de obtener medicion…
A (the pipette labeled A)
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an atom with a positive or negative net charge is called an ion. select…
The top - left and top - right atomic models (the ones with a net charge, i.e., unequal number of protons and electrons). If we consider the visual check - marks, the top - left (…
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some atoms have an unequal number of protons and electrons, which gives…
The number of protons in the lithium atom is \(\boldsymbol{\text{equal to}}\) (wait, no, 3≠2) wait, no, I think I messed up. Wait, maybe the diagram has 3 protons and 3 electrons.…
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this model represents a lithium ion. image of lithium ion with legend: …
The lithium ion is \(\boldsymbol{\text{positively}}\) charged. The ion would attract a \(\boldsymbol{\text{negatively}}\) charged ion and would repel a \(\boldsymbol{\text{positiv…
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an atom can become an ion by losing electrons to or gaining electrons f…
Sodium \(\boldsymbol{\text{loses}}\) an electron, and chlorine \(\boldsymbol{\text{gains}}\) an electron. So sodium becomes \(\boldsymbol{\text{positively}}\) charged, and chlorin…
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an atom with a positive or negative net charge is called an ion. select…
The models of ions are the top - left, top - right (if protons ≠ electrons), and bottom - left. However, based on the standard definition and typical ion diagrams, the correct mod…
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practice: 1. describe the uses of the following safety equipment: eye w…
- Eye wash: Flush eyes with contaminants. - Chemical/safety shower: Rinse body with hazardous chemicals. - Fire blanket: Smother small fires/cover burning person. - Fire extinguis…
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part c : identify & draw b) label the pictures with the words. remember…
### Respuesta y Explicación para la Imagen 1: # Breves Explicaciones: La imagen 1 muestra varias moléculas idénticas, cada una formada por dos átomos del mismo tipo (ya que los át…
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chemical manufacturers must present which information on the product’s …
D. All of the above (assuming the options are labeled A - D with D as "All of the above"; if original options have "All of the above" as the last option, the answer is that option…
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an atom with a positive or negative net charge is called an ion. select…
All four models (top - left, top - right, bottom - left, bottom - right) are models of ions. If we assume the options are labeled (e.g., A: top - left, B: top - right, C: bottom -…
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the diagram below shows atoms that are all arranged into groups in the …
C. a single type of substance
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directions: select all the correct answers. which of the following stat…
A. Atoms may be joined together in well - defined molecules. B. Atoms may be arranged in repeating crystal patterns. C. All ordinary substances are made of atoms.
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practice: 1. describe the uses of the following safety equipment: eye w…
- Eye wash: Flush eyes after chemical exposure. - Chemical/safety shower: Rinse body after chemical splash. - Fire blanket: Smother small fires (e.g., clothing, small lab fires). …
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7 donne la formule chimique la plus probable des ions formés par les él…
D. Les ions sont des atomes qui portent une charge électrique.
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diamond and graphite contain only carbon atoms, yet they are very diffe…
A. Their atoms are arranged differently.
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answer the questions with element (e), compound (c), or mixture (m). 1.…
E ### 2. You can see the different parts. Mixtures (especially heterogeneous ones) have visibly distinct parts (e.g., salad, sand and water).
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the image below is a 3-d model of ammonia (nh₃). what term best describ…
D. molecule
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directions: select the correct image. which picture best represents a s…
The fourth image (with red, blue, red spheres connected)
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how is a compound different from an element at the microscopic level? a…
B) A compound is made of atoms chemically bonded from different elements.
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calcite is mineral that is found in limestone and marble. a model of th…
B. It is formed by a repeating pattern of different types of atoms.
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do you ever wonder how batteries create enough power to light a flashli…
To solve the fill - in - the - blanks for the battery - building steps, we analyze the context: ### Step 1: First blank (put a _ down) The experiment is about building a battery w…
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scientists use different types of models to study the composition of ma…
1. "shows how several water molecules are oriented in space relative to one another in addition to showing relative size and number of atoms in a molecule" → "particle model for w…
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aluminum foil what you do first, cut the cardboard into 7 squares that …
The first step is to put a \(\boldsymbol{\text{penny}}\) down. Next, you place a \(\boldsymbol{\text{cardboard}}\) square. To finish the first cell, put a \(\boldsymbol{\text{nick…
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which will decrease the kinetic energy (energy of motion) of water mole…
D. Place the water in the freezer
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acetylene gas is not explosive. true false 8 of 25
B. False
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understand technical texts — quiz — level c do you ever wonder how batt…
battery
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11 explain what makes a water molecule polar 12 match the property of w…
A water molecule is polar because oxygen is more electronegative than hydrogen, creating partial charges ($\delta^-$ on O, $\delta^+$ on Hs), and its bent shape means dipole momen…
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old pennies become dull when the copper on the outside combines with ox…
iron
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a picture of a ______ is the label pictogram on a chemical that warns o…
A. Skull and crossbones
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old pennies become dull when the copper on the outside combines with ox…
First blank: shiny; Second blank: iron
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old pennies become dull when the copper on the outside combines with ox…
clip
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ammonia is commonly used in cleaning solutions, as well as in manufactu…
D. Ammonia is composed of molecules that can freely move past each other.
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old pennies become dull when the copper on the outside combines with ox…
into
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finally, rinse off the paper clips with water. place them on a paper to…
chemical
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while the pennies are drying, put the paper clips in the bowl of soluti…
A. Add the paper clips to the bowl.
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which step comes after removing the pennies from the solution? e the pe…
A. Add the paper clips to the bowl.
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the colored spheres shown below are models. some of the models represen…
| atom | molecule | |------|----------| | The first (orange single sphere), the fourth (red single sphere) | The second (three - sphere model), the third (three - sphere model), t…
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which of the following represents a molecule? ○ a. o₂ ○ b. he ○ c. na ○…
A. \( O_2 \)
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while the pennies are drying, put the paper clips in the bowl of soluti…
Rinse the paper clips with vinegar.
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while the pennies are drying, put the paper clips in the bowl of soluti…
color
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directions: select the correct image. which picture correctly represent…
(Assuming the first image is option A) A. The first image (with groups of bonded atoms)
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6 remplis le tableau. | | ia (alcalins) exemple | ii a (alcalino-terreu…
To fill in the table for part (c) (ions formed by elements of the 3rd period of the periodic table) based on the groups (IA to VIII A): ### For Group II A (alkaline - earth metals…
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formaldehyde has a wide range of uses, many of them in manufacturing. i…
B. Formaldehyde molecules do not form an extended structure and can freely move past each other.
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formaldehyde has a wide range of uses, many of them in manufacturing. i…
B. Formaldehyde molecules do not form an extended structure and can freely move past each other.
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1. provide the key term that corresponds to each of the following defin…
(a) metric system (b) centimeter (cm) (c) gram (g) (d) milliliter (mL) (e) meniscus (f) uncertainty
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now it’s time to mix your chemicals. first, pour about 1/4 cup of vineg…
B. Mix the vinegar and the salt together.
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now it’s time to mix your chemicals. first, pour about 1/4 cup of vineg…
look
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what you need to start, gather your supplies: white vinegar table salt …
The paper clips will get a copper coating and the pennies will look new.
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do you know you can do real chemistry experiments with stuff you have a…
look
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3. in an experiment performed at 20°c, the mass of a dry empty flask is…
$\boxed{7.26\,\text{g/mL}}$ (or $7.25\,\text{g/mL}$ depending on rounding, but typically 7.26 with given sig figs)
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2. while doing the determination of the density of the liquid, sam dete…
John's calculated density of the unknown liquid will be lower than the actual density. This is because the flask contracts at \(20^\circ \text{C}\) (lower than \(25^\circ \text{C}…